There's not much worth going out of your way to play on the #Gizmondo but Trailblazer is definitely one such game.

It's a remake of an old C64 game where you steer a rolling wheel down a track, avoiding hazards and using jumps and boosts to get the best times possible. It's simple, but still holds up really well!

https://www.youtube.com/watch?v=8VkJ7T8tvAA

Gizmondo - Trailblazer

YouTube
There was a similar-but-different Trailblazer remake for PSP Minis, with different levels and mechanics, but the Gizmondo version actually runs at a much higher framerate, and IMO has the better set of levels, even though it lacks widescreen like the PSP remake.
On paper the Gizmondo is more powerful than the PSP, but you wouldn't know it looking at the library. Because the Giz never really had new releases beyond the launch lineup, and because the dev tools seem to be cobbled-together dev tools with an inefficient modified WinCE OS, there wasn't much that could take advantage of its performance.

But here we have it, perhaps the only case where a mostly-similar game was released on Giz and PSP, and the Giz version comes out on top!

#Gizmondo

Unfortunately there's no good way to play this right now unless you own a real Gizmondo, but there is an emulator currently in development - hopefully it is one day finished and released!

http://tuxality.net/projects/rapier_gizmondo_emulator

Rapier - Gizmondo multiplatform emulator / Windows CE subsystem reimplementation - Tuxality Goodies

Tuxality Goodies.