Another arcade shoot-em-up on the Xbox 360? This one lets you warp your Galaga-style spaceship from the bottom of the screen (shooting up) to the top (shooting down). Crossfire is in the Xbox Live Indie Games channel for $3.
I'd write you folks some impressions, but I only played it briefly last night. Good first impression but nothing you can't figure out from the video. Try the free demo version at least.