BusBus.in offers details of bus routes in Chennai, Mumbai and Bangalore (I read about this site on PluGGd.in).

As I imagine some people will view bus route details while they're on the go, I think a mobile-friendly version of this type of website is important. I like the auto-suggest feature on this website.

As pointed out in the post by Pluggd.in, ideally the site should also provide bus times and frequency of arrival/departure. Hopefully, it's just a matter of time before we see such features.

I couldn't really see this type of information anywhere else on the web (although it may exist). Once India's road transport corporations become more established on the internet, perhaps they'll also provide similar information?