Depending on your motor you could go with someones old android phone or a small android tablet and power cable. either a bluetooth OBD2 dongle or a micro/mini USB to OBD2 port cable. Then run Torque or similar ap.
just about as sleek as you could get and still be less than what is on the market.
just about as sleek as you could get and still be less than what is on the market.