What's your favorite bukkit plugin?

[iNinetails]

Hey guys! I'm looking to find the most liked plugins and the most useful plugins directly from YOU! I have a long list of plugins I like, but here's the short version:

• Citizens 2 (with compatible builder plugin)
• Essentials
• ChestShop

Those are my top 3, go ahead and list yours or list all of the plugins you like!