To take that a step further, Continuum Analytics has a product called Wakari[1] that is pretty much a web-based, sandboxed, nicely glued together version of everything mentioned in this thread: python environment, IDE, IPython notebook, interactive plotting, collaborative sharing, SSH console, file manager, dataset manager. It hooks into various APIs, S3, etc., and based on my usage so far it is very good UI/UX decisions... almost as if actual scientists designed it.
Of course, it is not free! Right now it's in beta and (I think) anyone can try it though. I'm not sure what their plan is for pricing, although I do believe they mentioned a local install option for clients who don't want their data walking out of the building.
(I am in no way affiliated)
[1] http://www.wakari.io