Last year I upgraded my home office router. I bought the Linksys E4200, which was top of the line at the time. It has an elegant design, but it has some trouble staying cool. I had somewhat resolved the problem by hanging it sideways (I had it hang by the sprouting Ethernet cables). This, coupled with the ceiling fan did a reasonable job at keeping it from overheating.
It was just the right size for my router and at $7.99 the price was right.
I lay my router flat on the chill mat and connected the two via the router's USB port. The dual fans of the Targus chill mat started spinning quietly. Now my router stays cool as a cucumber.