I tried to install a very late version of Mac OS X, version 10.6.0. I was hopeful that this would be easy. It wasn't. The guide I followed was for the HP Mini 1000, and apparently it does not apply to my HP Mini 110. I was able to fill the SDHC card with the installer DVD image, and run the patching program on the image, but it causes a kernel panic in the HP Mini when it tries to boot from the (patched) SDHC card. I can't find anything online which even points at a possible cause or solution.
Now I'm going to try version 10.5.8, but I have some doubts about this. More as I explore...