We covered Allwinner D1s RISC-V processor with 64MB built-in RAM a few days ago, and we’ve just found out about Xassette-Asterisk, an open-source hardware board based on the processor that runs Linux (OpenWrt) and is said to cost less than $10 to make.
This is significantly cheaper than the Allwinner D1 based Nezha RISC-V Linux SBC currently sold for a little over $100, a rather poor value. The cheaper board will not quite have the same applications with just 64 MB RAM and no HDMI, but it could be great for projects requiring a camera and/or a display, audio interfaces, plus some I/Os.