Drinking coffee and listening to Scoble’s video on Twitter.
For future reference ( or never 
cos I don’t feel like installing any of these now):
There’s a desktop client for Twitter called Spaz. Downside: you need to download 9 megs of Adobe AIR beforehand.
Twitter.pbwiki.com lists a long list of Twitter apps.
Here’s a description how to set up TwitterVision as your Windows XP desktop.
If you do try Spaz, please let me know what you think (good and bad) — I appreciate and respond to all feedback.
Thanks!
Hi - I think my favourite so far has got to be the TwitterBar Firefox add-in which lets you post straight from the address bar.