You can upload a Mp3 file to a photo sharing website like Flickr, or Picassa,. For this you need an image and the Mp3 file you want to up[load.

1. Go to Command Prompt (Start => Run => Type cmd => Press enter) or (Start => Programs => Accessories =>  Command Prompt)

2. Switch to the folder where the image and music file is

3.  run the following command on the command prompt now

copy /picture.jpg + song.mp3 picture_to_upload.jpg

4. When you want to download that MP3 file from Flickr, open the relevant photo page, go to “All Sizes” and download the original sized image. Change the file extension to MP3 and enjoy the music using Winamp (This kind of files won’t play in QuickTime or Windows Media Player.)

Ref: Digital Inspiration