WHere can I get more Scientific Tools (college/grad/research level)

I am using the main, universe, multiverse and restricted; however ubuntu doesnt have an enormous amount of advanced science tools. There are some fiels they have alot of, but some very limited. Thjere are a couple of cool chemistry tools, but I am look for stuff like 3d simulation of neurons, and so on. Does anyone know of any repositories where I can find more science tools?

Thanks, Jordan

Not a respository as such, but gets one started with knowing what to look for ...

http://sal.iatp.by/