Oh dear, but I guess we were all a bit impressed the first time we discovered the Test+Off button! Is there a way to stop the annoying 5 seconds of "Test" when you press the button to see if the ATIS is coming in and discover its not?!
I'm not that long on the 737 myself, can't think of much else except:
Some people think running 1 Pack in Auto and one off on the ground saves fuel, but obviously the logic will make it run in high flow which burns more APU fuel than both in auto. Check out the MAINT/APU page and look at the instant fuel flow in the different configurations.
I think everyone knows the abeam point in the legs page, just put the point on top, then the point below on top of that and execute it.
The FMC info is always interesting, would be interested to hear any other little tricks.