Always a good catch all when it goes a tad quiet:
Fuel - Change tanks
Fuel - Pump On (or off in some cases)
Mixture - Adjust
Mags - Check both or try one then the other
Easy to remember FUEL, FUEL, MIXTURE, MAGS... Flows nicely
Guess what - it covers all of the most common forms of stoppage that are likely to be rectifiable before impact.
Not a complete panacea but useful, I'd suggest.