Ever realized you needed a document that was on a different computer from the one you were on? With Sync, you can access your files from anywhere. * Keep all your files in sync * Use Sync to mirror your most important folders -- like your Favorites, Pictures, and Documents -- so they're the same on all your computers. * Sharing files is easier than ever * Sharing with friends, coworkers, and family is easy when you add and update files in a shared folder. Large files? Not a problem - Sync can handle files up to 4 GBs in size. And it works on both PC and Mac (support for Mac is available in English only). * Get to your files when you're away from home * Install Sync on your computers to instantly access your files from anywhere.
… More
Edit
I've been using this ever since it was called FolderShare. It's a phenomenally brilliant way of keeping an array of folders on an array of computers continually up to date. Whether it's a team of people working on a project, a folder full of website files or if you need a quick way of transferring 300gig of data between machines. Works on Mac or PC and I love it.