Isn't UPX a really bad idea under jffs?
It is still possible to save 200-300K on a 1MB file (UPX has better compression than jffs2), but the CPU/RAM cost of UPX may outweigh the benefit.
I finally went to download "my" mplayer, and it wasn't there! EDIT: I can't PM qwerty12 either, his inbox is too full.