Sometimes I want to be able to adjust the temperature of my printing on the fly. Is there a way to do this with up and down buttons, (similar to speed) so doing it without having to open up the gcode data entry window and typing in M109 S? Lazy, I know! 
Second this. I’ve been meaning to ask about it myself.
pronterface has a temperature input window and temp drop down box.
ok, added to the feature candidate list.