Dropbox - online storage, file sharing, data syncing (syncs 1Password across my Macs and iPhone)
Droplr - I use it for uploading pics and screenshots to numerous places
CloudApp - same as Droplr but I use this more and it has a nice web interface as well
ShoveBox - has become my go to notes/snippet keeper. Had it for almost a year before I really started using it but happy I did.
Caffeine - keeps my MacBook Pro awake
MainMenu - great utility to fix permissions, force quit apps, eject volumes, clear cache, and tons more
iStat Menus - I use it for battery because of the drop down it provides that has all my diagnostic info as well
Standard AirPort, Volume, Clock and Spotlight
(From Bostonguy3737)