LeapFrog Pollux Platform: STC
Here's a port  of a simple game, STC  ("simple tetris clone") that you can install and run on your device provided that it's set up with a framebuffer driver and libSDL rather than the original graphics drivers and Brio. See those howto guides first.
You can obtain the source code from github. For example:
git clone clone git://github.com/yurovsky/lx-stc.git cd lx-stc
Before building lx-stc, make sure that you've copied the SDL header files to some location, for example a rootfs directory containing /usr/include/sdl. Replace "/path/to/rootfs" with that path below and change the name of your toolchain as needed. Then build the game:
CROSS_COMPILE=arm-linux-uclibcgnueabi- ROOTFS_PATH=/path/to/rootfs make
If successful, you'll see ./sdl-stc. Copy that binary to /usr/bin on your device and copy the .bmp files in ./bin/sdl to /usr/share on your device so that you have:
/usr/bin/sdl-stc /usr/share/back.bmp /usr/share/blocks.bmp /usr/share/numbers.bmp
On your device, simply run:
to play the game. Press the "home" button on your device to exit.