Greg, It sounds like you are interested in doing amateur breeding to create your "own" variety of tomatoes. It sounds like fun to me, and one of these seasons (maybe even this one) I am going to do some crossing too. It's also a great way to teach kids about biology, genetics, etc. To get you started, I recommend a book by Carol Deppe, "Create Your Own Vegetable Varieties". Your local library should have a copy. It's a very informative and practical lesson on breeding all sorts of veggies, including tomatoes. Forgive me if someone has already made this recommendation; I've been having problems getting my tomato digests lately and this is the first one I've read in a while. But yeah, I guess you can't call it an heirloom until it's been handed down to someone. Good luck! Matt Gibbs