Map: http://www.bungie.net/Forums/posts.aspx?postID=15190465
Gametype: http://www.bungie.net/Forums/posts.aspx?postID=15190323
This is a map made specifically for Mongoose racing around the perimeter of The Pit. If you download the gametype, the game will be similar to Rocket Race in that each team has a VIP and a Mongoose. However, instead of a rocket launcher, each player starts with a sniper rifle and a shotgun with unlimited ammo. The person riding on the back of the Mongoose will be firing, while the other drives. Also, the checkpoints (Go-To points) light up in a specific order, so the flow of the map should always be one way, making it a real race. The first person to reach 25 checkpoints wins. In the beginning, one team will inevitably be nearer to the first checkpoint than others, but it's easy to catch up. Shield recharge rate is at 200%, so only sniper headshots, and point-blank shotgun shots will kill, much like if you were inside a regenerator field. If you die, you will respawn out of the track (or near it), and can wait for your teammate to pick you up. If you look at the screenshots, you'll notice that it's fairly easy to get out of the race track. While this won't earn you points at first, it can actually be turned into a strategy. On person might stay out of the map and cover their VIP (VIPs can drive in the game variant), but if their VIP gets into a fight with another 'Goose, it's pretty much over. As a result, staying on the track is recommended. Now, for said screenshots:

[img width=800 height=600]http://i256.photobucket.com/albums/hh194/ssshakedown-/Halo%203%20Map%20Screenshots/14823103-Full.jpg
The area between the needler spawn on the default map configuration, and the default shotgun spawn on the default configuration. In this screenshot, the flow of the track would be from right to left.
[img width=800 height=600]http://i256.photobucket.com/albums/hh194/ssshakedown-/Halo%203%20Map%20Screenshots/14823119-Full.jpg
The area between the default needler spawn and the default rocket spawn. Again, right to left.

[img width=800 height=600]http://i256.photobucket.com/albums/hh194/ssshakedown-/Halo%203%20Map%20Screenshots/14823208-Full.jpg
Between the mauler and shotgun default spawns. Right to left.

[img width=800 height=600]http://i256.photobucket.com/albums/hh194/ssshakedown-/Halo%203%20Map%20Screenshots/14823209-Full.jpg
A mongoose spawn.

[img width=800 height=600]http://i256.photobucket.com/albums/hh194/ssshakedown-/Halo%203%20Map%20Screenshots/14823270-Full.jpg
The tower area. Bottom to top.