[Dyne]

Camino, for web browser.

http://www.caminobrowser.org

And customizeable too.

http://www.pimpmycamino.com/

Your one-stop wallpaper source. Nothing else even comes close.

http://interfacelift.com/wallpaper/i...&w=2560&h=1600

And here's a good site.

http://applepedia.com/Post_Install

EDIT: Oh, and iConcertCal. Who doesn't want to see what upcoming concerts there are, personalized to your own tastes?

http://www.iconcertcal.com/