If your laptop is running hot, or you just want to elevate it a little a bit, grab a couple of forks.
This video from the MAD Science Hacks shows you all you need to know. Lay out two forks -- prong side down -- and make sure the distance between them is about the width of your laptop. Gently rest your laptop on top of them and you're all set. I tried it out myself and it actually works pretty well. It isn't the most elegant solution, and not ideal for long term use, but it's one of the easiest DIY options out there when you're in a pinch. Just don't try it on your lap.
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