I think your problem is warping that lifts a corner or end off the countertop. I'm told that thicker (1/2" or more) cutting boards will not warp as much...or, at all. Also, there are different grades of polyethylene plastic used in cutting boards. The high-density polyethylene material is supposed to be more dimensionally stable and cutting boards made from it are not supposed to warp, especially if they are at least 1/2" thick.
My chef source says that washing cutting boards in a dishwasher will cause them to warp because they are exposed to high temperatures for an extended period of time. While washing a cutting board with hot water is a recommended practice, exposing it to heat for more than a brief period (like had washing) will cause warping.
I like the bamboo cutting board,
@Neal; looks like a good solution. For those looking for high-end cutting boards, check out the Epicurean line:
Amazon.com: epicurean cutting boards
TJ