Laptop tend to heat up more when their bottom rests directly on a solid surface. While fans my never kick in unless doing some hard gaming, I tried a few of the support designs online. Most are cool, but bulky or simply don't fit. So, I made my own, based on several that I saw. My design includes the few details I liked, a few of my own, including the perfect opening for my specific laptop, which is about 13 mm at its thickest points. With that in mind, I've included 3 versions of the Laptop Lift Foot (12mm, 13mm, 15mm).

The sizes all give 15 to 17mm of lift, but the opening / mouth where it clamps onto the laptop varies with the version. My laptop is just over 13mm, so that is the original clamp size, which doesn't slip, since the opening is a little smaller than the laptop body, making it grip, keeping the foot in place when moving the laptop.

Laptop Lift Foot - 12mm, 13mm, and 15mm mouths.