I try to avoid Simpson products when I can, but a couple years ago when I looked they were the only ones with Carbon X socks, so I bought some. Really like them:
http://www.saferacer.com/simpson-carbon ... uctid=1060Their "one size fits all" even worked on my size 14 feet just fine. I do have some "normal" Nomex socks, but like Bernie, never felt like they were worth much. The Carbon X socks seem much better in terms of thickness, and supposedly are more wicking than Nomex. They certainly don't wick like Smartwool or other truly "tech" fabrics, but seem the best of the fireproof stuff.
But like Bernie, I try not to trust socks anyway. I use high-top shoes and they go above the cuff on my suit. The shoe tongues have small areas of lesser protection, though, so I like having a good fireproof sock. I'm not convinced it's much better than a good cotton pair, but since they actually fit well and felt good, I went with them.
I use Oakley Carbon X boxers, too, and have found I really like the Sparco Carmythe longer underpants on top of that along with the Carmythe shirt. And Carbon X balaclava. I *hate* balaclavas, but after Espenlaub's fire incident and seeing that every pro driver I know wears one whether the series requires it or not, well, I wear one, too. There's just so much room for fire to get under your helmet, and I can't imagine the pain you'd be in with neck burns.
--Donnie