As twitter become more and more popular and so the applications built on top of Twitter. Twittershare is the latest service built up on Twitter API that allows you to share files of up to 10MB using Twitter.
Pownce allows you to share files with powncers, till now it is not possible to share files with twitter. With twittershare you can share anything you want like music, video, pictures of up to 10mb in size.
Desktop client is available for Mac users to share files, Windows users can use the web interface, the desktop app is on the way.