On the twistedmetal.com website, there was a "car customizer" that allowed you to design a skin for your favorite vehicle that could be imported into Twisted Metal for in-game play on your PS3. The site had a "Photoshop-like" feature that allows you to paint and design a skin for all the vehicles available in Twisted Metal. You could also download the "skin templates" so that you can edit them with your favorite graphics software on your computer. Once you complete your edits on your computer to the skin, just upload them to twistedmetal.com and then into the game for play on your PlayStation 3.
Note: The Twisted Metal Website is gone, instead "www.twistedmetal.com" brings you to a 404 page on www.playstation.com.
Gallery of Designs
In the Car Customizer section on twistedmetal.com, there was a Gallery which displays the Highest Rated, Most Recent, and Most Added to Profiles categories of designs created by other players. You could add these skins to your Garage for your own in-game play in Twisted Metal on your PS3.