Utilities:

Remote (connect to iTunes on my home network)
Shazam (recognize songs)
Facebook
TweetDeck (Twitter client)
Pandora (listen to tunes)
P-Calc Lite (decent RPN calculator)
Instapaper (read web sites that I flag for later reading in my browser)
Skype (when traveling abroad, seems to work)

Eye candy:

Bloom, Air, and Trope (ambient music gadgets written by/with Brian Eno -- my daughter digs these)