Some pretty remedial ones for the R22/R44:
On approach,
check 3-2-1 to avoid settling with power: Rate of descent less than 300 fpm whenever using >20% power and below 10 KIAS. It's not perfect and a bit conservative, but it's a good pre-landing check. (And for better or worse, this or some variation is drilled into most students' heads.)
The
fuel gages show your endurance: a full main tank is good for 2 hours and a full auxiliary is good for an hour.
For hover autos...well, this isn't a rule of thumb really, but
throttle-pedal, settle-pull. It's just a good way to break that maneuver down.
I think this is a good thread...the other one was more tongue-in-cheek (and already 6 pages!).