nosing through their bedrooms

Have sex!

Matti, that was my first thought too. Good answer but not the right one.

Take a nap

The Reader's Digest survey is incorrect!! :)

search their computers
eat junk food for dinner (what DH and I always did)

walk around in their undies?

When my kids left for school I always played a few rounds of a video game called Kaboom! Didn't want them to know I wasted time playing games.

I was going to say play with their toys.

My first thought was having sex, too but I think it's snooping in the kids room. Be it diaries or computers or looking for playboys under the mattress. LOL