Sobees is an interesting twitter and Facebook app that runs in a browser. Sobees is based on Silverlight 3 plugin released recently by Microsoft. Sobees is an web based app but there is a desktop cousin to it.
Sobees supports multiple twitter accounts, if you have different accounts for different purposes you can setup all of them in side by side panels and update them. The template option allows you to organize the space, as you can see from the below image, it has several template formats.
You can see your friends twitter stream, your stream, replies and DMs conveniently using the tabs and navigation icons on each panel. The more useful and interesting feature is the anti-spam blocking that allows you to block spammy tweets using a keyword. If you donâ€
It also supports real-time search that is not just specific to twitter, it also searches Freindfeed and Oneriot. OneRiot is a real-time search engine if you donâ€
Overall this is a nice web based twitter client with enough features to manage multiple twitter accounts. If you donâ€