Pac-Pix was a Pac-Man spinoff released in 2005 for the Nintendo DS. While the DS had a very lackluster first year, there were some interesting spin-offs and unique games for the platform. Pac-Pix was certainly one of them, and it's probably the most distinctive of the franchise.
The game is no simple Pac-Man game. There's no mazes or patterns to master. Pac-Man doesn't exist in the game until you draw him with a stylus. Depending on the size of Pac-Man, he will be stronger or faster. The majority of the game was clearing levels by devouring ghosts.
Pac-Pix met a really mixed reaction critically. It's gotten everything from superb recommendations to abysmal rants. Because of this, I never really jumped up to go get Pac-Pix. I contemplated about getting it for a few years, but always passed the chance. I do admit I admire the uniqueness and style.