This plastic laptop stand features two cooling fans powered from your MacBook's USB port. Connect it using the USB cable supplied and they circulate the air nicely. The build quality is acceptable, and it's agreeably light.
However, while it works well as an on-the-desk laptop riser and the fans promote airflow, it does little to cool the CPU.
We ran a distributed computing application to keep the processor running at full capacity, then took its temperature at intervals using iStat Pro, with and without the mat, and again with it but turned the fans off. The difference was negligible. Suspecting a fault we got another, but the results were the same.
Targus Chill Mat for Mac works as an ergonomic stand to prevent wrist ache. It's also useful for protecting surfaces from heat damage and keeping legs cool when using a MacBook on your lap, but as a CPU cooler, it's a non-starter.