I've lost count of how many Portal styled map manipulation flash game spinoffs I've posted for Monday Mind Teasers, but I have yet to find one I didn't like. It's impressive how many different directions the mechanic can be taken in by so many different designers.
Fault Line is a bit like Paper Mario, but instead of bending Mario around to get into tricky areas in a level, you're actually folding the map to help the main character advance through a level. This mechanic has been done a few times before in various Paper Mario games as well, but to have a whole game dedicated to the gameplay concept is a lot of fun.
Even though it's not a very difficult game, there's 30 total levels to entertain you. The audio isn't as great as some of the games I've posted this year, but the controls are very pleasing; I hate when games have walk and run animations that feel like you're a slug crawling across the screen.
You can play Fault Line here on Nitrome.