For those "Patched" Servers. I found an easy way to dupe from the auction board with this tool. It's not duping as you would expect.
What I have done is while you have one character acting like an farmbot in a starter town, have another client running in a party with the first character. before you start the bot to farm, move the second character to ah. then press F6 to start the bot on the first character.
Go to the auction board and buy something with the second character. DO NOT remove the item from the auction board after you buy it.
After you buy the item, use a movement rune on the second character, move it to the first character. The second character should have a disconnection error and you get kicked from the game. The character with the bot running will not get kicked off the server.
Log you second character back on. You should still have your gold that you started out with in AH, and when you check the AH auction board, you purchase should be in there ready for you to collect.
*** This has not always worked on all servers. Try with something cheap. On some servers I have lost the gold and the item I purchased.***
This does work on about 5 out of 6 patched servers I tested it on. Works great while dual boxing!