I'm running a 24/7, no lag (95% of the time) server. It's freebuild with pvp, a mob arena, and running bukkit. Some of our plugins are:
iConomy
Essentials
Mob Disguise.
We have already got many devoted members, so you probably won't be alone if you join. The IP is 83.222.240.167:31165. Come and join us!