Hair dryer as towel warmer
During the colder months, my kids shiver pathetically when they emerge from the bath. That two minutes of towel-drying time is torture for them: their teeth chatter and they looked like drowned rodents.
To help ease the chills, I use the blow dryer to warm up their towels (I'm sitting there anyway). Once they're out of the bath, I point the dryer at their towel-wrapped bodies and blast them with hot air. Lots of "ahhhhhhs" follow.
Caution: Be extremely careful with this hack. Only point the blow dryer at skin covered with a towel, and keep the dryer moving. That air will burn if held too close or too long. Also, be exceedingly careful when using any electrical appliance near a filled bathtub (or splashing kids). Unplug as soon as you're done.