Posterous: post anything to the web

Posterous is a new simple web service for when you need to post anything to the web to make it publicly available to anyone: photos, videos, MP3 and all kinds of files.

The good part: no signup is needed. Just send an e-mail to post@posterous.com (remember to attach any files you want to post) and you'll (almost) immediately receive a reply with the address of the website where your files are posted.