Off the top of my head, in order.
Blades in the Dark - I want to try this both for the game and the system. No DM though I can get players.
Apocalypse World - never played the granddaddy, and I haven't played any post-apocalyptic games in over a decade.
Dogs in the Vineyard - okay, this goes waaaay back. Would like to play it with a DM who groks the concept, very different than D&D.
Unknown Armies - love fiction like this, esp. Tim Powers, wonder how well it translates into an RPG.
7th Sea (2nd) - Just to give it a try. Have a friend who teases running it. A one shot or single adventure would be enough.
Gumshoe - outside my normal genres, want to give it a try. Like 7th Sea, a one shot or adventure is fine, no need for a campaign.
Cortex Prime - kickstarted it, waiting on final.
Also been jonesing for some good SF/Space Opera (not licensed IP) and some drama-filled superhero, both campaign length, but without specific system requirements.
EDIT: 13th Age - where I can be a player instead of DM.
EDIT^2: Someone else mentioned For the Queen. I'm waiting for delivery of that as we speak. So I guess that should have been on my list.