I finally implemented an idea I came up with a while back. Cloud source code backup!
Update: I am now using SpiderOak in a similar manner as Wuala is no longer free.
I configured Wuala to cloud store (encrypted) my source code directory. It allows you to filter directory names and file names (with wildcard), so I took out images, EXEs, DLLs etc, so it is pretty much just source code I might change. You can also take out projects you aren't modifying, eg source code from a third party library. One nice trick is to see what will be filtered via a tree view is to use the add file dialog which will re-calculate each time it is opened.
It becomes my backup in case anything dies before it gets into proper source control... or any project stuff that isn't in source control and could easily be put back (eg root level Visual Studio solution files) . Particulary handy as sometimes I also make projects and the way I ended up configuring Git means I sometimes need to make a new repository in BitBucket (which is annoying as there are a few steps). So this is also a backup if I can't be bothered at the time (sometimes I might ditch an idea/ change a project structure).
My source folder was around 1.5 gig, I think it got down to 24 meg with my filtering.