Much like GMailFS and the Gmail Shell Extension that were discussed previously, RoamDrive allows users to store files using the free space available on their Hotmail accounts. Unlike the other two, however, RoamDrive can store files without any size restrictions and has features like automatic compression. The developers also plan on releasing a "Pro" version that supports Gmail and Yahoo Mail, and can link your Hotmail, Gmail and Yahoo accounts for a massive amount of storage.
ed. Is it only a matter of time before email companies start cracking down on this?