Online file sharing suggestions? (PPT)

[Tron_fdc]

Looking for a free online file sharing service suggestion. I'm currently working in a group project for University, where we are spread out geographically across Western Canada. We need a service that is:

a) free
b) able to hold multiple files (mainly powerpoints)
c) ability to edit realtime and track changes
d) free

Only 4 users. We are building powerpoints throughout the week with different sections assigned to different individuals, and because of our work schedules/locations we are doing it all at different times. We have been using email, but it's a huge PITA to track when each person is sending 3 or 4 revisions every day.

I looked at yousendit and dropbox and had a go at google docs, but I'm wondering what else is out there.

Anyone have any suggestions?

[DownInFlames]

If you're doing Powerpoint the first thing I would try is Microsoft's SkyDrive.

http://windows.microsoft.com/en-CA/skydrive/dropbox

[Iceman90]

Microsoft SkyDrive, Dropbox, Box.net are all good choices.

Google Docs might be the best choice, if you need a presentation, but not necesarily PowerPoint.