Techcrunch has an interesting review of LogMeIn’s new file sync service, Cubby. I haven’t seen the service yet but it looks like most of the others, right down to the free 5 GB starter storage. One big difference is that, while you can sync from your computer to the cloud, you can also synchronize just between your own computers. This cloudless option is reminiscent of Crashplan’s backup, where you can either use the cloud or rely on your own hardware.
Cubby is still in beta but it would definitely be worth taking a look. There is an iOS and an Android app for mobile access.