It's not quite "retro" in the same sense, but I used to run Debian on a Zipit Z2 handheld computer as a daily driver. The CPU was a respectable 312Mhz ARM, but it only had 32Mb of RAM. X11 ran like a dog, but it was a perfectly functional machine if you stuck to the command line. It'd even compile software, provided it was written in C and not C++. This was around 2010.<p>I doubt you'd get any "mainstream" distros to run on it now, much less Debian. The bloat is real.