i got a technician at college to make one up for me.

it pulled my second lambda sensor out of the gas stream enough to trick the ecu.
cause before i got it made, the senor was all over the place. 100mV, 400mV,700mV! (got a 200cell cat) now its a steady 40mV,60mV (cant remember what it actually was, but mechanic reckons its spot on now)
if he is up for making some, would there be any interest?
this is all dependant on if he can do it, and what he would charge. dont think it would be much. prob £5 - £10.