Speaking of hot, have you ever grown mustard greens? I used to grow them organicly, and they were much, much hotter than the wimpy stuff at the store. The spice goes right up your sinuses like carbonation! This is the stuff the Chinese make that hot mustard with. ( i.e. real mustard)
Sorry if my comment came out confusing - I was talking about cherry peppers, not cherry tomatoes. As to cross-species things, I do know that you can't grow tomatoes or eggplants near tobacco - can't remember all the whys about that off the top of my head but it has to do with the nicotine in the members of the nightshade family (tomato and eggplant among them)
Not only have I never grown mustard greens, I've never even tasted them to my knowlege.
By organic, I take it you mean without chemical fertilizers, and weed or pest killers? If so, that's my garden.