Now, don't get me wrong. Betta splendens is a lovely fish. I have 7 of them (1 male, 6 females) and I couldn't be happier. However, unless you're talking serious show fish (You know: white dragon royal blue over half moon with a side of chips and a coke) they're pretty common.
I saw down the page a way that someone had some Betta imbellis. I saw some Betta pugnax come up at an auction a couple months ago. There was a story in TFH now long ago about wild bettas in Indonesia, including, among others, Betta coccina, and then there are giant bettas and tiger bettas and 40 or 50 other species.
So Who's keeping the odd bettas? The rare bettas? The bettas who live together in peace, enjoy fast water, mouthbrood, and have people saying, "That's no betta; that's some sort of miniature snakehead?"
What do you like about them? How do you keep them and breed them?
Spend a few minutes to tell an appreciative audience who have probably had a few more than enough fin rot threads for the nonce.