HIRENS BOOT CD - All in One Bootable CD which has all these utilities. For complete list visit:

As it is a bootable CD, it can be useful even if the primary operating system cannot be booted
Video
VLC Media Player - When installing set this to play all video formats by default and never worry about any video codec problems ever again.
Images
Irfanview - When installing set this to open all image formats by default and never worry about googling an image format to find something capable of viewing it again.
GIMP - Open source photo-shop (very powerful image editing program free of charge)
Archiving/Compression
WINRAR
Tugzip - Deals with almost any file compression known to man.
Total Commander - a file manager that will eliminate some of others separate applications (no more need ftp, compression tool and others cuz this are already in). a must have (and use)
Virtual Drivers
ALCOHOL 120 - I prefer this one I think its much better. I have found Daemon tools can carry malware in its download.
POWER ISO - just as good if not better then 120.
Messaging
Pidgin IM - contains basically every chat program. Install GFire for limited XFire support as well.
Trillian - A great alternative to pidgin
Office
Open Office - free office suite like Microsoft office.
Internet Browsers
Firefox
Google Chrome
FTP Clients
FireFTP (Addon for Firefox) - simple but effective for those who just need limited functionality
Voice Communications
Ventrilo
Teamspeak
GSC
Torrent
uTorrent - light weight bit torrent client often used as an alternative download source
Burning software
Nero Burning ROM (not Nero Express)
ConvertXtoDVD
Power-ISO
Updated list:
System Rescue / Boot:
Darik's Boot and Nuke Boot disc that wipes drives.

DrWebCureIt! Antivirus and a live rescue CD.

EasyBCD Windows bootloader manager.

Hiren's Boot Disk/CD Recovery and rescue apps on bootable USB/CD.

Ophcrack Windows password retriever and live CD.
Torrent Related:
΅Torrent Torrent client.

Magnetizer Converts torrent files into magnet links.
P2P:
Soulseek P2P app.
NFO Viewer:
Hash Checking:
Easy SFV Creator Creates and reads SFV files.
Operating Systems:
BSOD Info:
BlueScreenView View BSOD info.
OS Tweakers for OS and Browsers:
Bootvis Provide faster XP boot and resume times.

Download 99 shortcuts for Win 7

Drivetoys

Tweak UI Tweaks for XP.

Ultimate Windows Tweaker Tweaks for Vista and 7.

VistaGlazz Vista theme tweaker.

Windows Live Free add-ons and apps from MS.

Windows Start Button Changer Change the start button without replacing the explorer.exe and system .bmp files.

Xdn Tweaker Tweaks for Windows.

XP Visual Styler XP themes/tweaks.
System Information:
Bootracer Boot speed.

CoreTemp Monitor CPU temperature.

CPU-Z System information.

Everest Ultimate Diagnostics, benchmarks, and monitoring.

GPU-Z Video card and GPU information.

HWMonitor CPUID Hardware monitoring program.

OCCT CPU stability testing program for overclocks.

PC Wizard 2010 System information.

SiSandra Diagnostic tools for testing your system.

SIW System Information for Windows.

Speccy System information.

Speedfan Monitors voltages, fan speeds, and temperatures.

Seconia PSI Security tool designed to detect vulnerable and out-dated programs and plug-ins.

Taskill Process viewer and killer.

What's Running Inspect and edit your Processes, Services, Modules, dll:s, IP-Connections, Drivers, Startup Programs, Memory, Processor.
WinDirStat Disc usage stats and clean-up.
Antivirus and/or Firewall:
Avira Antivirus.

Avira Premium Security Antivirus.

COMODO Firewall

DrWebCureIt! Antivirus and a live rescue CD.

ESET Smart Security 4 Firewall and antivirus.

FortiClient Firewall and antivirus.

Microsoft Security Essentials Antivirus.

Nod32 Antivirus.

Returnil Antivirus with rollback.
Spyware and Malware:
Antiy Ghostbusters Malware/spyware remover.

ComboFix Spyware remover.

HiJackThis Malware/spyware remover.

Malwarebytes Malware/spyware remover.

Returnil Virtual environment, anti-malware, restore.

RootRepeal Rootkit detector.

Spybot Search & Destroy Spyware remover.

SuperAntiSpyware
Browsers:
Firefox Browser.

Addons for Firefox:

Addons posted: AdBlock, NoScript, Download Status Bar, Gmail Checker, Webpage screenshot, Smoothscroll, Chrome Gestures, GleeBox, Better Gmail, Docs PDF Powerpoint Viewer, FastestChrome, LastPass, WOT, AdThwart, Google Translator, CustomizeGoogle, SecureLogin, Classic Compact Theme, IE Tab, All In One Sidebar, SpeedyFox, Read It Later, Readability, Skipscreen
Google Chrome Browser.
Backups:
Acronis True Image Disc imaging.

DriveImage XML Backup and recovery.

GetDataBack Data Recovery.

Macrium Reflect Disc imaging.

Norton Ghost

Paragon Backup and Recovery v10.1 Free
Partitioning:
Easeus Partition Master
Security:
Start-Up Managers:
RunAlyzer Autostart & configuration manager.

System Ninja Start-up manager, process manager, CCEnhancer, and more.

TuneUp Start-up manager with misc optimization tools.
Cleaners:
ATF Cleaner Cleaner.

CCleaner Cleaner.

CCEnhancer Support for more apps in CCleaner.

Fcleaner Cleaner.

NTREGOPT Registry optimizer up to XP.
Defraggers:
Defraggler

PerfectDisk

Puran Defrag
Data Recovery:
Recuva File recovery.

Restoration File recovery.
Uninstallers:
Revo Uninstaller
Portable Apps:
Computer Repair Utility Kit 57 portable computer repair tools for a USB.

Puppy Linux on USB

SpaceSniffer Portable application that lets you understand how folders and files are structured on your disks.
Remotes:
Proxy Pro Remote access for Win, Mac, and Linux.

TeamViewer Remote access and sharing.
Programming:
JAVA
Server Related:
Windows Server 2003 Resource Kit Tools
Virtual Boxes / Emulator:
DeepFreeze Virtual environment.

Returnil Virtual environment, anti-malware, restore.

Sandboxie Install and run apps in virtual environment.

ShadowDefender Virtual environment.

VMware Virtualization software.
Network and/or VPN Related:
Broadband Tests and Tools

DNS Jumper Troubleshooting DNS issues as well as setting up a home network.

or

or

Doctor Ping compare your ping.

Doctor TCP Windows utility for modifying your TCP stack.

MurGeeMon Network controller, login controller, and other utilities.

Tweak Test Test if your computer is setup correctly for broadband TCP connectivity.
FTP/SSH/SFTP/SCP:
FileZilla FTP client.
Usenet:
Alt.binz Usenet client.
Retrieve Product Keys:
Magical Jelly Bean Keyfinder Retrieves product keys.

Ophcrack Windows password retriever and live CD.

Windows Key Finder Windows key finder in XP. Vista, and 7.
Retrieve Lost Passwords / Password Managers:
KeePass Password manager.

PC CMOS Cleaner Displays BIOS passwords and can reset to default.
Archive Packing and Extracting:
7zip Archive utility.

Universal Extractor Archive utility.

WinRAR Archive utility.
Parity Utilities:
QuickPar Verify, repair, and create PAR2 files.
Various Utilities:
Allmyapps Auto app installer. Useful after a clean install.

Driverpack Solution Install and update drivers.

DriverScanner 2010 Scans your computer to provide a list of drivers that need to be updated.

FixWin Utility Repair & fix common Windows annoyances & issues.

Glary Utilities Various useful and free utilities.

Input Director Use one kb/mouse for input into multi PCs.

Install-Block Admin tool.

JitBit Macro Recorder Macro utility.

Launchy Keystroke launcher.

Macro Express Macro utility.

Ninite Auto app installer. Great after a clean install.

Process Hacker Manipulating processes and services.

Quick Macros Macro utility.

Rizones Power Tools Various Windows utilities.

SOFTCAT free edition Organize software and store serials.

Workspace Macro Pro Macro utility.

Zapmessenger Erases traces of uninstalled messengers.

Zint Barcode Studio Sorts just about any type of barcode including QR codes.
Image File Mounting / Building / Burning:
Acronis True Image Disc imaging.

Daemon Tools Lite Mount ISOs.

Gizmo Drive Mount image files.

ImgBurn Burn, build image files.

ISO Recorder Create and burn ISO's.

Macrium Reflect Disc imaging.

Pismo File Mount Audit Mount image files.

Virtual CloneDrive Mount image files.
Gaming:
CD / DVD / Blu-Ray Ripping, Converting, Burning, Extracting:
Applian Recording Suite Download, capture, record, and convert video/audio from web sites.

AShampoo Burning Studio CD/DVD/Blu Ray burner.

Burrrn Tool for creating audio CDs with CD-Text from various audio files.

ConvertXtoDVD Video converter and burner.

DVD Decrypter DVD ripper.

DVD Shrink DVD backup.

DVDFab Remove DRM and backup DVD.

Exact Audio Copy (EAC) CD ripper.

Handbrake Video ripper.

iWisoft Free video converter and editor.

mkv2vob Coverts MKV files to play on PS3.

Nero Video editing, burning, and backup.

Sonne DVD Burner DVD. ISO, and Video_TS burning.

Sony Vegas Video, audio, and blu-ray creation and production.

Super C Music/video encoder and renderer.

Xilisoft Video Converter
Media Players:
Aimp2 Audio player.

Foobar Audio player.

GomPlayer Video player.

KMPlayer Video player.

WinAmp Audio/Video player and streamer.
Codec Info Tools (Audio/Video):
Audio Identifier Audio inspector.

CodecInstaller Codec analysis.

GSpot Codec analysis.

MediaInfo For seeing what's inside media files.

Sherlock Codec analysis.
Codec Packs (Audio/Video):
CCCP Codecs.

K-Lite Codec Packs
Codecs (Audio/Video):
FLAC-Free Lossless Audio Codec

Real Alternative Play RealMedia files.
I am not responsible for the misuse of any of these programs. If you don't know how to use them do some research