I have 2, an Odroid XU4 and a raspberry pi zero.
My odroid is running retropie for retro gaming, runs really smooth. In a standard case, removed the original heatsink and glued on a think passive one. Temps are high but it's very stable.
My raspberry pi is also running retropie, I also glued a heatsink to it so I can overclock it, but ever since I got the odroid up and running, it's been stored away. But I used an old NES controller as a case. But I did use it quite a bit and it overclocks nicely to 1.2Ghz with a heatsink.