I think about Haunting all the time. It was so different and weird. I miss that era of experimental gameplay.
Excite Truck was legitimately amazing. The absolute definition of a flawed gem. I have never had another racing game that scratched that kind of intense itch. I remember the rush I would get when hitting my spins in the air and hitting a perfect landing. The gameplay was different from any other racing game, where boost states are occasional flourishes. In Excite Truck, the goal is to stay in a boost state (by performing tricks and nailing landings/drifts) for as much of the race as possible. Also, the fact that it supported custom soundtracks added so much to the game. Nothing in Excite Bots could compare to racing on Mars with Freebird blaring as I'm doing 1080 spins in a monster truck in super low gravity.
I went to a cousin's house who had this game and I was blown away by it. It had basically Mario Odyssey's capture mechanic, laid on top a tight, beautiful, polished platformer created by Capcom during its peak.
I hope that the Switch is a big success, because one thing I loved about the Wii era was how all of these weird games found a home in the HD era. I hope that the Switch carries on the PSX>PS2>Wii legacy of bonkers games that don't require the highest graphical fidelity.
To add to the conversation, I am probably one of the few that remembers
Guardian War for the 3DO
It was a weird action RPG with a super unique artstyle. I wouldn't say that it was good by today's standards, but for the time of its release it was notable.
Also, I would like to remember
Elemental Gimmick Gear or E.G.G. for the Dreamcast
It had this beautiful hand-drawn art and top-down Zelda like gameplay. I remember playing it for a little while, but getting confused about where to go. It did leave an impression on me though for the short time I spent with it.