A way to share files across your own computers, or even with other people (say, getting around email size limits). I believe there are even clients for smartphones, etc.
Sign-up, and we each get 250MB of extra storage (looks like it starts at 2GB).
Replacement for whatever current thing we use (anymore ... ?)
Diogenes of Sinope: "It is not that I am mad, it is only that my head is different from yours."
Arnold Judas Rimmer, BSC, SSC: "Better dead than smeg."
I've been using a primitive version of this on my home LAN. I have a folder on the server called "XFER" that is shared with every other PC I allow onto the network that I use to move files around. This way I am not opening any particular computer's entire C drive to any other computer.
I signed up, but I'm not exactly sure how or why I will be using it, yet.
"Be bold, and mighty forces will come to your aid."
I think the idea is mostly for people with mobile gadgets/portable laptops. Cloud-based storage for easy retrieval. They appear to have Blackberry, iPod, and Android clients.