This is an excellent site. I think it’s based on a childrens’ TV show, but rather than being packed with the usual thinly-disguised marketing material, the Boohbah web site has great, educational content instead.
It’s very well suited to young or special needs children, but it’s also quite pleasant to pointlessly wander around if you’re an adult. The animations are soothing and abstract. it’s one of the rare occassions when a confusing Flash-based site is a good thing.