"At it's most basic level, Wuala is an online storage service.
Like other services it aims to allow you to access your files from
anywhere, even if your home or office computer is turned off. You
can store any file in your Wuala 'drive' and they can be any size
(up to your storage limit, of course).
"The big difference that sets Wuala apart from other offerings,
such as Amazon's S3, is that Wuala is peer-to-peer. The developers
of Wuala have adapted many of the ideas of peer-to-peer systems
such as bittorrent to make your data both highly available and fast
to download. When you upload files to your Wuala account they are
first encrypted before they leave your system and then multiple
copies are split between several different Wuala users. The
redundancy is calculated via some custom algorithms created by the
developers that factor in things such as the uptime of the remote
node, bandwidth, historical reliability, and location. More
information on the science behind Wuala is available in the form of
a presentation from one of the developers..."