the interesting part about Rensenware is that as far as I know, it doesn't come with the game on its own, yet I vividly remember trying to play it. my best guess is that was a very deliberate prank set up by someone on some file sharing place or something.
I've tried most of the better known danmakufu games, one of the mahjong games, thoroughly hooked right now on Lost Branch of Legend, and watched a friend play Artificial Dream in Arcadia. Plus a random dozen of other small games from gamejams and such. Asprey on youtube also covers a lot of fan content, so I watch them once in a while.
(Imaginary Power of Meiji xx by Ashiyama Yoshinori)