A few weeks ago there were twelve varieties of summer squash at the local farmers markets. Saturday there were fourteen from a single grower. I've been experimenting with trying different varieties. Until this year I'd been aware of about three or, at most, four varieties. They were all somewhat bland. Lately I've been enjoying the Costata Romanesco for it's firmer txture and greater taste compared to a typical zucchini. If you've not tried 'em, and if you can get them nice and fresh, you may be in for a treat. Look for them at your local farmers market or well-stocked produce section at your regular market. I just grated up some to use in a frittata - it really takes to cooking better than regular zucchini, holding its shape and texture a lot more, and is, imo, much more flavorful.
http://home.earthlink.net/~ebay-pics/squash.jpg
If you try a few, let us know what you think,
Shel