Which are free upload and share web sites?

I know rapidshare, but it allows only 10 downloads; and I guess it removes the file after some days.

Are there any sites according to file types? such as photobucket and picasa for photos.

Sending through emails allows maximum 20 MB (e.g. gmail), and it won’t be helpful for some times like when I want to share a file here on fluther.

Any suggestions?