Free? No chance. Many of them would be completely useless, though, could be considered as deceptive advertising (or what 's the right English phrase for that), imagine realestate.free
free not only sounds like a spam but probably requiring an annoying plugin like the one for .shop, .aero .club and other twisted pseudo-domains around.
There are probably a handful of really good words that you could flip fast for a few grand if you could get them, examples: sex.free, mp3.free, poker.free, etc.