Touhou mother -- is a neat touhou and earthbound delirative... derelative... secondary work, has an english translation by vgboy/vgperson, and a neat walkthrough by the developer himself on nicovideo. It used to had a really fun walkthrough on translator's youtube channel, but youtube being youtube, the entire channel one day went puff without a warning.
Fantasy Explorer Nitroid -- an open world 2d puzzle platformer. This game requires balls of steel to play. Has a nice letsplay by raocow, a guy famous for his love of selftorture, probably because he became famous by ripping a nicovideo letsplay of vip mario 2, another game for true masochists. The music in this game is really good.
Megamari -- touhou megaman. Game by Tasogare Frontier. A megaman game with a very small hitbox feels surprisingly good. I never got past Suika in it. It has an interesting speedrunning tool for it written in asm somewhere on touhouwiki, it allows recording replays for this game.
There was some danmaku platformer, forgot the name of it, where you played as Marisa and waited for a chance to get closer to touhous to beat the shit out of them with your broom. There are a lot of danmakufu scripts, of various quality. There was that yukkurihead game, first level looked really epic, after that the wow factor got to the usual doujin quality.
Rigurui -- or リグルイ -- a cozy sfw visual novel about Wriggle. I thought it was a thriller at first, lol. I don't think it was translated yet.
Touhou Kenchinroku -- a really fun series of visual novels about an adult video cameraman getting gapped into Gensoukyou. Art quality is kind of meh in the first game, but in the second and third it can rival professional works. Writing is also really fun. It seems the author realized that drawing doujinshi is easier and pays about as much, which is why he stopped making games.