My Gefore 8400 GS graphics card's fan is broken, so my GPU's core temperature is going up to 95°C in normal use. Gaming brings it up to 125°C sometimes, which is the "slowdown threshold" (thanks, Nvidia!) to protect against burning plastic.
So here's my new, ultra-tweaked screensaver command:
wormhole -root -delay 34426 -zspeed 2 -stars 7 -fps
Wormhole is part of the "xscreensaver" package (on my Ubuntu it installs in /usr/lib/xscreensaver/wormhole).
It runs at 28fps at 3% CPU use of my Intel Dual Core 2 something something.
Don't know how much GPU it uses but it stays pretty cool now (about 92°C at the moment).
Pretty good, right ?