Mini-Challenge: Microwave

Microwave a bowl of water (add some citrus or vinegar if you have it on hand) for 2-3 minutes. While the water is heating up, wipe down the outside of your microwave. Once the microwave is done, (carefully) open the door, take out the bowl of water, and wipe down the inside. The steam will have loosened up a lot of the caked-on crud.