An Accidental Memory in the Case of Death has always been my favorite of his, but Copia is a close second. I didn't really like Similes much at all when I first heard it because of the vocals, but it grew on me over time. I'm guessing this new track means a new album is on it's way soon?
wonk is the only other person here that I know enjoys Eluvium, but if you're a fan of ambient and piano music you should definitely check this guy out. Best sleepytime/reading/studying music ever. Here's a new track from him: