http://www.getdropbox.com
You get 2G of space. Anything in the Dropbox folder is mirrored to the website (and then down to your other computers, great for sharing a master password file between home/work).
Anything placed in the Public sub-folder has a world wide interwebs link, ala sendspace.com. Like my new nephew Mitchell:
http://dl.getdropbox.com/u/212911/Mitchell%204%20hours%20old.jpg