Skunk Works had an employee incentive programme for those working on the U2 - for every pound of weight saved on the aircraft they would get $150. I can't remember the exact figures but once the plane got over something like sixty thousand feet every pound saved added an additional something like 100 feet to the maximum achievable altitude.
U2 pilots on the spy missions were extremely well paid.....a $40,000 bonus (a fortune at the time) was payable if, and only if, they completed their full tour of operations!!
Most of the Me109 prototypes were fitted with Rolls Royce Kestrel engines.
After WW2 Spain built Me109s under licence...these were mainly fitted with Rolls Royce Merlin engines, although some had the totally unsuitable Juno engine originally used in the He111