American McGee's Alice: Wonderland (Charm) gone horribly wrong. StrangeCharm overload in a psychological nitemare in Alice's own head. Beautifully disturbing twisted remake of a children's classic. The aesthetics alone are worth a play. (Unrelated note, McGee's next project involves distorting the Oz stories)
Alpha Centauri: Crash-landed factions contest over a living planet. Heavily posthuman technologies. The FMVs playing upon acquiring Secret Projects often have interesting imagery. Also see [an alternative faction pack] for less clichearchetypal factions.
Fallout: Asthetically Down or at times Strange with beautiful hints of Up, and includes physical modifications and xenobiological beings and transformations.
Planescape: Torment: A computer adaption of the Planescape RPG, just as funky. Mind-warping philosophy, alternative Down aesthetics (Sigil is a cool city), reality malleable by beliefs, strange cast of characters, death as a mere inconvenience.
Septerra Core: Life and adventure in a world orrery powered by magic, featuring xenobiological transformation, mindgames, alien forms of communication, and a really fancy machine gun.
Any game by Phillipe Ulrich (Exxos), especially [Captain Blood], Kult, and Extase. Highly future-surrealistic. Amiga versions preferable. (Certainly preferable to the PC versions, though Blood certainly felt like an ST port to me, and most Blood fan sites claim better audio on the ST.)
Roleplaying
Elizabeth McCoy and Walter Milliken, GURPS: Illuminati University
David Pulver and Mark MacKinnon, BESM: Big Eyes Small Mouth: Anime role-playing in its truest form - Echo
David Pulver, GURPS Transhuman Space:
David Pulver, GURPS Bio-tech: Vastly informative, from Brain Tapes/Programing to Xenosculpting!
TSR, Planescape: A setting consisting of multiple planes expressing sheer concepts or fundamental elemental realities, with a city called Sigil on the top of an infinitely tall spire.
Kult: A game in which the central premise is that God has imprisoned all His rivals in space-time, and only by going mad and seeing through the cracks in reality do the players have a hope of escaping their confinement and realizing their own inner godhood. Or something to that effect.
Console
Devil May Cry (1 and 2): Demon fights other demons, including magma-scorpions, monsters made of buildings, and more. Gothic halls that breathe and ripple, castles overgrown with membranes, doors guarded by giant spirit-hands. Inspiration for Strange, Fever Cathedral, perhaps more.
Klonoa 2: Lunatea's Veil: Very Charm, with a good dose of the other Warps dropped in. A doglike character dreams himself into a broken world of cute furry people, and travels across the various Warp-like lands to awaken the nightmare realm from its tearful slumber so that he can confront its king.
NiGHTS: Free-flying on rails, perhaps the only game to get as close as possible to flying in dreamscapes without actually being asleep.
The Silent Hill series: so very, very Strange
Sonic Advance 2(GBA): Specifically the Music Plant levels, I felt it to be particularly Charm. Sonic Adventures have a similar look and feel--the crazed looping freeways above the city levels would be perfect inspiration for ZipWays.