I love the Zoo Tycoon series, raising and caring for zoo animals. I was thrilled to get a DS version to carry around. The implementation on the DS is a bit flawed, though.

Zoo Keeper is a simple puzzle game for the DS that is fun for casually passing the time. It´s great for kids, but might get monotonous for adults.

Zombie Dash is a simple side-scrolling game where you blast away at zombies. It's simple, mindless fun, and you can pass a few minutes in line or on a bus working to beat your previous high score.

A direct GBA translation of the Yu-Gi-Oh! card game.

Yoshi Topsy Turvy GBA has a built in gyroscope sensor that is much smaller than the similar Wario game. This lets you actually tilt your GBA unit to play the game.

I love the Worms series. If you remember the old cannon games where you adjust the angle of fire and let loose, this is the same idea - but 100 times funnier!

Word Search for the droid is a great way to keep your little grey cells active, to pass the time in an entertaining way, and perhaps to learn a few new words!

Wipeout Pure is the Pod Racer game for the Sony PSP. Coming from a 10 year line of Wipeout racing games, the transition to PSP is almost flawless.

I love puzzle games. Where's My Water by Disney is a fun puzzle-style game which has you directing flowing water from a source to a destination, to help fill a crocodile's bathtub.

Where's My Perry is a water-based puzzle game very much like Where's My Water. You're trying to redirect water to a destination to help your secret agent escape.