One thing I've always wanted to do is have a hanging basket of fresh herbs, ready to pick whenever I want (even in the dead of winter). I think I'm getting closer.
A continuous green onion supply!
I fished these out of the back of the fridge, cut the wilted tops off and put them in a little vase with water and some marbles to hold them somewhat upright. Eventually they will grow so much that I'll have to water them every day, and the marbles will get overgrown with roots. I'm not sure how much green onions cost at the store, but whatever it is, these cost less. It's basically a free source of fresh vegetation.
Warning: Be aware that these are onions and, depending on the size of the room, could make it stink like onions. If you put it in the laundry room, it might smell like BO. Just a thought.