do you know how to have this: http://community.mybb.com/thread-159715.html
(user can choose the background in own profile, like Covers on Facebook: http://99covers.com/
but with input (file/url) like in Xthreads newthread input file?
Because with that tutorial you have directly link (hotlink) from other website, and it's not very good.
Then for my server space will be a disaster (they are huge images) but I hope not all my users will add a background