To specify, IDM, or "intelligent dance music" as many critics and journalists call it, is any electronically based music that eschews the party vibe and emphasis on driving beats, unlike its more popular cousin EDM.
Most of the artists like to experiment with different textures, sounds, and production methods, and many of them sound completely different from each other.
Popular artists include Aphex Twin, Boards of Canada, Autechre, Squarepusher, Four Tet, Venetian Snares, Plaid, and many, many others.
I'm hoping to get a running thread going where we talk about this stuff. Sometimes I feel like the only one who likes it.