Before I knew her, my friend R went on our favorite radio show (Too Beautiful to Live) and encouraged people to begin their own worm farms. It planted a seed in my head even though I was an apartment dweller with no need for soil at the time.
As soon as I bought my house with the intention of having an organic garden, I knew I would have to get some composting worms.
If you have an interest in creating some good soil for your garden or potted plants and/or want to reduce the amount of waste you throw into a landfill, then composting worms are an ideal solution. They take up little space, are relatively inexpensive, and can be kept indoors.
You can make your own worm bin for under $50, but I chose to go with the Worm Factory, which I bought at Ace Hardware for under $100.
It came with stacking bins, a spigot for collecting "worm tea" (a nutrient rich water, used as a fertilizer), bedding... basically, everything you need to get started, except for the worms. You can order the worms directly from Ace or search for another seller online.
It takes months for the worms to make enough castings (i.e. worm poo / soil) to put in the garden. I'm basically waiting for next year to use the soil.
When I told him about the worms, my Uncle J said I now have livestock. That cracked me up... it's probably the only livestock I can handle, but it's perfect for urban dwellers.