"Here’s a little secret no one seems to know about (or at least before this post!). There is a Skype robot which will post to your Twitter account.Here are the simple instructions:

1. Add twitter4skype as a contact.
2. Type the following as a single chat message to twitter4skype:
   
   /account (shift+return)
   yourtwitteraccountname (shift+return)
   yourtwitteraccountpassword (shift+return)

    

3. The system should return: twitter4skype Registration complete!
4. The next time you write a chat message to twitter4skype, the entry will appear on your account and you’ll receive your friends’ twitters in Skype.

Tupalo is a social word of mouth recommendations network for fans of local culture, mom and pop boutiques and things that make you go "hmm". Now you can Tweet from within a location page in Tupalo.

See link for details on how to twitter from Facebook.

Fring integrates Twitter with free SMS updates

Netvibes Twitter
"Update your status at Twitter directly from your Netvibes homepage."

Twapper
allows you to integrate you 30 boxes and Twitter accounts