For me it's:
Pure Calendar / Pure Grid Calendar / Forecast (everything by the developer Koxx!)
Abduction World Attack
Listen (by Google)
Nimbuzz (until Skype can get themselves in gear and release their own proper app)
Spare Parts (to speed up screen switches and turn on the groovy screen flip)
Nimbuzz doesn't log into facebook for me. It then opened a chat with someone named facebook asking for my birthdate. the user was offline, but thought I'd ask here if that's how its supposed to work.