Have you been over to the Only Connect site recently ? The link is in my recommended links. The walls have been updated , and they're addictive. I idly went over to try out just a couple, and two hours later I was still there, and had to drag myself away to watch J.K. Rowling's Who Do You Think You Are ?
You can also submit your own walls for potential inclusion on the site - I may be wrong, but I think this is a new feature. Good fun, and well worth a look.