I used it as my main DE a few years ago, its great! Really cool UI, completely different to all other DE’s but it makes sense, and it has some cool stylings like for example virtual desktops icons being the actual desktops, just really tiny. The bugs, however, kept piling up, and it (segmentation fault)ed too often, so I had to abandon it. Last I heard, the reason it doesn’t get major dev work anymore is that its really hard to work with.
I suppose Rigs of Rods fits the bill, although I never played it.