Chez Scheme (the compiled version vs. Petite Chez) figures high on those lists, and it was just opensourced by Cisco. I used to use Gambit-C, and I still like it, but Chez is fast.

It is and regularly way above the others. I had to hold on my fanaticism.

I am playing with Eduardo Cavazos's libraries with Chez [1], and particularly the port of xspringies. Great fun considering as he points out that the mass-spring calcs are all taking place in scheme. It runs fine on my 2-3 year old notebook.

C was a third language for me in the day, and I like Lisps, so this Lispy-C thing is going to eat my afternoon up!

[1] https://github.com/dharmatech?tab=repositories

That would be ecraven (who hangs out in #scheme on Freenode). See also: https://github.com/ecraven/r7rs-benchmarks