I did that a few years ago for a semi-bricked WM8850 netbook which I can't reflash with Uberoid, a custom Android for these ARM machines. So I set up a VFAT partition with the kernel, a boot image file, and maybe I'll add some Void Linux root filesystem on an ext3 partition tomorrow. It's worse because booting from an SD card is not very realiable, but it's better than nothing.