So the trading thing. I guess if I give 50 GB to the cloud that is used by other people via the Wuala cloud? Or is it for my own use only?
I currently use mozy of offsite backup and could possibly ditch that for this and have my work in one place sync'd which would be pretty cool.
Not quite sure what you're asking... as I understand it, the (say) 50GB that you allocate is used by... well, anyone I suppose - it's just encrypted data which contributes to the sum total of the cloud, with no way of knowing what it is or who it belongs to (the possible liability implications are dealt with in the documentation, basically it's a non-issue). You could even delete your local cache entirely (eg when you reformat), and as long as you continue to make the space *available* it won't affect your own online entitlement. There's a slight gotcha with that though - if you have more than 20GB of your own data online, apparently you'd need to wait for the cache to "refill" before you regain write access, although this probably wouldn't take too long, and if you keep the local cache somewhere sensible on a different partition (it's user-configurable), it's unlikely to be any sort of problem.
Similarly, your own data could be almost anywhere, divided up amongst many other members, again presumably with plenty of redundancy for when individuals become unavailable for whatever reason, whether temporarily or permanently.
I suppose the cost (or lack thereof) is the killer feature... if you allocate 100GB out of a 1TB drive, it would equate to a one-off payment of about £4 at today's prices, which compares pretty nicely to DropBox at $19.99 *per month* for 100GB of online storage. On the other hand, you'll constantly be using a certain amount of bandwidth by making your drive space available to the cloud, and there's the cost of keeping your PC powered up for between 7 and 24 hours/day (again, a non-issue if you'd be doing this anyway).
I've only just come across the scheme myself, and to be honest I haven't had time to look into it in depth, so maybe there are showstopping downsides I haven't noticed yet (hopefully not). It's definitely an interesting concept, anyway.