Tenebrix network is flaking on me presently. Fairbrix seems stable, though. Who's mining these coins?

No problem, the dev says about 1.5 mils of the premine are set aside to help recruit developers and sustain support for no less than 6 year. Unfortunately he was last active on August 10, 2013. Things don't seem to have changed much since Tenebrix was released.
Q: I heard you premined, you bad bad person...
A: Well yes, I premined 7 million coins. Why so many - well, to be completely blunt and honest, I got a bit tired of a discussion of how much should one premine that I had going on and used the premine value from GeistGeld. Perhaps not the wisest decision, but worry not though - I will use 2 millions do fuel verry slow (no more than 4 TBX per user, may get less if their price rises) faucets with strong user ID (Google Acc + captchas), and about 1.5 mils are set aside to help recruit developers and sustain support for no less than 6 years (you gotta agree that it is a looong road and a lot of money-gulping things can happen)
Interesting to see that the dev was looking six years ahead. He must be very disappointed to see what his coin has now become.

But on the bright side, Litcoin probably wouldn't exist today if Tenebrix and Fairbrix had never existed so he still played an important part in the history of cryptos.
Is there a Windows client? Would like to play with this.
Seconded. OP's link to binaries for Windows brings up a 404 error. The source is available on GitHub but I don't have a C++ compiler with me right now and I'd rather not bother with compiling it myself. I could find references to something on the Internet called "Ufasoft Coin" which seems to have supported TBX at one time (and the dev seems legitimate and posts on these forums) but the version that supported it has been removed from their homepage.
EDIT: I'll see if I can compile it myself and I'll post the binaries here. I'm not sure if the thing will even work though since there might not be enough available nodes. The network is pretty much dead I think.
EDIT 2: Scratch that. I think I found the Windows binaries. They're here:
http://github.com/Lolcust/Tenebrix/downloadsEDIT 3: Just tested it and yup, I was right. No nodes so it's stuck at block 156:
