I like ones that have really good pictures and clear directions. You Grow Girl by Gayla Trails is aimed at the beginner urban gardener.
Edibles, because you get a great return on investment: food. Peaches - unfortunately they're only in season for 3 weeks at a time, but man, what a glorious 3 weeks it is!
I am a huge fiend of the truffle. Problem is, it is breaking my bank. I want truffles in everything I eat: truffle fries, truffles in pasta, truffles on pizza, truffles on fish, etc.
I've heard of people composting urine. That seems a little...extreme.
For me, loquats, and the grapevine is starting to come back.
I have not seen this yet, but the Huntington Gardens has a plant known as the Corpse Flower, which rarely blooms, but when it does it smells like decaying carrion.