So what are they? On the PS2, the games would be Burnout: Revenge and SSX 3. Ramming into cars is a favourite (virtual) past time of mine, and the undulating snowy peaks provide a serene facade to what is a technically challenging, thrill of a ride.
Geometry Wars: Galaxies looks set to join Mario Kart DS as my perennial favourites on the Nintendo DS. Both games possess the "plays well anywhere, anytime" quality that never goes away, and this is particularly true with regards to MKDS. Time will tell on whether Geometry Wars truly has that, but it is in good standing.
As for the Gameboy, it would be the all-time-classic Super Marios Bros. Speaking of old school consoles, Super Mario Bros 3 is my perennial favourite on the NES, and the same spot for the SNES is occupied by Gradius III, just what is this about sequels and their third incarnations eh?
I haven't really play my Dreamcast much ever since purchasing it, so no favourites here.
Last but not least, the Personal Computer. Do you know what game I can't get enough off for the PC? That would be Command and Conquer: Red Alert 2. The campy cut scenes, the crazy gameplay, and throwing in the even crazier expansion set Yuri's Revenge, and you get one heck of a weekend waster.
So, these are my perennial favourites? What about you?