I recently looked at moving from SanJose to Mountain View (aka closer to Google). The rents fell off approximately linearly with distance to MountainView. If you put a dollar amount to the falloff for a 2 bedroom... it corresponded to approximately $50-75 per hour of daily commute time. So you're "paying" $50-75/hr to live closer to work.

Using Oakland as an example (2 hours of commute daily * 20 days), that's ~$2000 less in monthly rent compared to a comparable place in MountainView. Which is about right...

[Assuming you moved into areas that weren't themselves local hotbeds such as SF, PaloAlto, or Atherton.]