If you haven't been using Drop.io you should. This is like the Swiss Army Knife of file sharing and they keep adding new features all the time. It's easy, you don't need to create an account, you can control privacy on drops, and you can even control how long a drop stays online.
An intriguing feature of Drop.io is the ability to add drops by phone, which are saved to your drop page as mp3 files. There's also number for conference calls, but these won't be recorded to your drop. I haven't tried it yet, but the fax option appears to be interesting as well. Faxes can come in and out of your drop. To receive a fax, however, the sender has to use a special cover sheet. I don't send faxes very often myself, but this will be handy when I have to, and I could do it easily from home instead of waiting until the next time I work.
Drop.io has recently added document viewing with Scribd's iPaper. Since iPaper is flash based, it allows people to view your documents even if they don't have a compatible program (Office 2003 vs. Office 2007 for example). I'm also a huge fan of Scribd and do enjoy it when things I like are compatible with one another.
I see a huge potential for Drop.io in the area of collaboration or group work, especially with so many different ways to connect to the drop.
