I've been trying to drive less lately, so for me, that means walking, biking, and using the VTA. However, getting somewhere on the VTA is only really useful if I already know where my target is and need to find the closest stop. If I instead need to find, say, a hardware store near a station, that involves a manual search by address, which is a pain in the ass; it'd be nice to have an interface that lets me pick, say, "hardware store near (any VTA stop)" or "hardware store near (this set of VTA stops)".
An obvious design goal is to make this extensible, so that you could drop in an include file for BART stops in SF, T stops in Boston and so on and so forth. Getting that to work from the initial search string shouldn't be too hard if it's possible to piggyback off Google's parser -- let Google find the city, then check for an appropriate include file, use it if there is one, kick back an error if not.
I might make it to SuperHappyDevHouse tonight; if so, this is what I'll be working on.
(Now, if only there were a good way to tell Google "and I'll be walking or biking from my start location, so quit giving me results that involve freeways...")