Tweet directly from Microsoft Outlook

TwInbox enables you to use Twitter directly from Microsoft Outlook. You can view your tweets and mentions and also post new tweets, replies and re-tweet posts. The program tightly integrates with Outlook and stores all your tweets in a selected Outlook folder, allowing you to archive, manage, group and search your tweets the same way you manage your email. Other features include support for keyword tracking, Twitter usage statistics, short URLs, picture upload, support for multiple account, and more.

• Update your Twitter status directly from Outlook.
• Receive your friend updates in Outlook.
• Archive, manage, group and search your tweets the
  same way you manage your email 
• Search, track keywords. TwInbox will automatically download ALL tweets matching the keywords you specify, even if you are not following the tweet sender. This feature is perfect for keeping up to date with the Twitter buzz on your name, brand, interests, etc.
• Group tweets by sender, topic, etc using the Search feature.
• Manage multiple Twitter accounts
• Upload and post picture files and Outlook email attachments.
• See new tweets at a glance.
• Assign custom folder and categories to new messages.
• Use Outlook's "Reply" and "ReplyAll" commands to send twitter direct messages and @replies.
• Automatically sort new tweets into per-sender folders.
• Shorten URLs with bit.ly.
• See graphs of your Twitter usage statistics.
• Tweets sent to you (@replies and direct) are marked with high importance, so you can see them at a glance.