Glide OS is a relatively popular “Cloud OS” which is like an operating system in the cloud. It provides you with a desktop and apps that are available from any browser. Its a cool idea but I have never used it myself since SugarSync is enough for me.
The team @BBOS spotted that Glide OS just released a free BlackBerry client for their service. It has limited support only for the BlackBerry Storm, Tour or Bold 9700 so older devices are left out in the cold. Still it might be worth checking out.