Automatically turn bluetooth on or off depending on current network (MBP running Lion)

ControlPlane is a supported development based on Marco Polo.

Once upon a time I was using the free app Macro Polo to do location-aware configuration changes on my MBPro. Sadly, it's not been supported or developed since Snow Leopard. It's still available to try though and it might work well enough on Snow Leopard or Lion to meet your needs. Worth a shot, costs you nothing but time really.

Locations 3 in the MAS purports to do all of the same things as Marco Polo. Included in the list of things it can change is enabling and disabling your BlueTooth radio. I haven't used it though so I can't speak to how well it works. If it's half as good as Marco Polo, it should be pretty useful.