I recently picked up a ROCK64 with 4Gb RAM to test it out as a fanless desktop computer. The ROCK64 is a credit card sized single board computer (SBC) like the Raspberry Pi. It's available with 1, 2, or 4Gb of RAM, and optional eMMC storage in addition to a microSD slot. The ROCK64 is fairly comparable to the Raspberry Pi 3 Model B+ except it does not have Wi-Fi, can be configured with much more RAM and supports 4K output over HDMI.
