Zamzar is a free online file conversion service. You can upload your files to ZamZar and select the format you want it to be converted,provide an e-mail id. You can convert hundreds of files formats,for example text, video,image files…etc. It even supports the 3gp file format for mobile phones.

It is just a 4 step process to get your converted file.
You need to provide an email-id to which the download link for the converted file will be sent.The catch here is that the file being uploaded should be less than 100MB and the converted file is available for download for only 24Hours after which it is automatically deleted.

The list of all the file formats supported is available here.

Home Page : http://www.zamzar.com/