I've bought many modern skirmish rules over the years, and of course downloaded a lot of free stuff from the internet.
That said, I'd probably downloaded the FUBAR rules before, without actually paying them much attention.
Having now read this 'one pager', I see a lot of things that are exciting for a set of skirmish rules; things that make more sense than force on force, or don't have the 'slowing' effects of arc of fire.
There's a wonderful activation system based on troop quality, which also neatly allows for loss of unit effectiveness based on inherent training and quality. There are 6mm, sci-fi and even medieval variants.
Some relevant links here:
We'll be trying these rules soon...some WWII action I think.