embarassedtobrag I'm a heavy Twitter user (I think 3rd ranked in Woodland Hills outside LA) and so I use TweetDeck - I found a great article on configuring it to use less API calls (yes, I need to post the link for that and one other page here, I'll do that moreembarassment.

Spaz is nice because its open source, but when I started I began using Twhirl, which I think is a much nicer client than Spaz and is just as simple to start using, for what its worth. Twhirl can also grow with you, and one thing it can do that TweetDeck cannot is access multiple Twitter accounts.