If you don't know what the game is about, it's based on Amplitude for the PS2... which was created by the team that made Guitar Hero later on.
The official AmplituDS website:
http://amplituds.drunkencoders.com
First off, the boxart.
Then, a couple of images:


And last, a couple of movies:
Movie 1
Movie 2
Hurry up to the AmplituDS site and get it!

Now, as for the model converter and viewer.
They both run on the NDS. How's that for portability?
The converter converts models in the .x format of a certain syntax to a .c file which contains a display list in an array.
You could use that .c file in your own homebrew projects.
The model viewer reads out that .c file, and also slaps on textures if you've put that in the same directory.
Check it out. It's worth it.
Direct link to the model converter and viewer.
Example models available (not to be used in your own projects):
