Concur and add
1) Remote - control your itunes library when your away from it...
2) MochaVNC - very cool vnc client with zooming.
3) NetNewsWire - RSS reader (linked to Newgator.com)
4) Fizz Weather - better than standard
5) Currency - xchange rates
and some not so important ones
5) Enigmo - like lemmings only more complicated and with amazing physics
6) Advent - Collosal Cave :)