Just a site I came across earlier today which (re)uploads the file you uploaded to multiple file upload sites (Megaupload, zSHARE, Sendspace, RapidShare were the ones used when I tried). Sendspace links weren’t working for me then (apparently being fixed) and Megaupload link only worked after some delay. Link to the site: Sharebee.com
I don’t have much use for it, but if you’re into uploading files for multiple users to download from, this site would definitely cut the amount of time spent uploading to each different service. ;)