Older BMWs have a fuel consumption gauge on the dash. Someone has already implemented a standalone boost gauge for this, however it should be a simple extension of VEMS to handle this gauge directly
Mattias also mentions this on his page.
MembersPage/MattiasSandgren/BmwEthirtyIx
A Canadian fellow developed his own circuitry to control the meter:
- Forum discussion http://www.e30tech.com/forum/viewtopic.php?t=35635
- 1st video http://www.youtube.com/watch?v=S5KwL2DUkro
- 2nd video http://www.youtube.com/watch?v=-6KX1V0j8bk