What are some ideal plants, flowers, herbs or vegetables to grow in a small area? I live in an apartment, and no free land to grow anything. I'd love to, and it would save money on groceries if I could grow my own food.

Also, what are some good plants and crops that don't require a lot of attention? I tend to be very busy, which could make me feel guilty about such a responsibility. Of course, I know they need water and sunlight, but I would prefer something that could store food and energy for days at a time.