Travelling in Mumbai is as much a pain as watching the Indian team play cricket. In both cases you don't have a choice - if you were able to afford a place close to your work place, then most probably, you would be owner of that company. And watching cricket is in the Indian DNA.
To make the travel hassles a bit lighter, here is a Mumbai Nagivator - I had used its earlier version, which was good too. This one looks like an improvement. There is also Mumbai local train timetable - Especially useful during the late night early morning hours.
Link through Anand
Old post about Mumbai and Pune maps.