The Hamster in the Microwave Trick in Maniac Mansion works like this:
1. Get the hamster.
2. Put it in the microwave. (This only works with certain characters; others say it's too cruel. Off the top of my head, Sid and Razor will do it.)
3. Give the remains to Weird Ed.
As a result of being dead, you get to play through the rest of the game as a ghost! Unfortunately, this never seemed to stop the Edisons from seeing you, but it was fun.