Box will let you sync across both Mac and PC, and it has apps for Android, iOS, Outlook, BlackBerry PlayBook and a bunch of other platforms listed here. To get yours, just head over to Box here, sign up for an account and enjoy.
This is basically free space for any system you could conceivably use. The only disadvantage is Box has an upload size limit of 250MB. But 50GB is a lot of space for zero money, and most competitors like Dropbox, for example, only give you 25GB gratis. And who doesn’t like free stuff? [Box via SlickDeals]