Michael, I don't know much about MP3s but I think that with some programs you can change settings like sample rates as you can with wav files and this will have an effect on the size of the file (and the quality of the sound). To the best of my knowledge MP3 is the most efficient encoding method.

The suggestion Mbo made sounds good. I joined a similar service about a week ago. I don't know how the compare but mine is htt://www.xdrive.com.

Another method I use to share files although smaller files is my own free web space - very handy for things like making a MIDI file available here.

I have not used ICQ for a transferring a file larger than about 2Mb but I have found their File Transfer very effective and I use it frequently.

Jon