Wow, you got lawyer-trolled! What a joke! I would counter-sue. Copyright infringement, abuse of process, and being a giant douche. I'm not sure the last one is illegal, but it should be. It's extortion! This guy, and his gas bag lawyer, are just jumping onto a bandwagon that threatens to become a wagon train. Copyright wars? Meet the "I break your copyright and now I'm gonna sue you too... Wars" (that's not as catchy.) Pretty soon we'll see PirateBay suing Paramount for using them to increase movie sales. YouTube will sue Congress, "SOPA and PIPA were just ploys to get people interested in the process!!! You owe us money for the civics lesson we were forced to give! AND ATTORNEY FEES as Sanctioned in USC 1117 see Johnson v Wanker (cir. 1969)
But seriously, I'm not a lawyer, I am not allowed to give legal advice. But, this is a BS suit. The number is just high enough to make the fees worth their time, but low enough that you might just say, "Fuck it I don't wanna deal with this shit!" And then, pay them. I applaud your response and approach. But you should really burn them. I bet if you started a fund for that, side by side of this one... you'd earn enough to have the papers prepared and filed. Should be an easy case. This guy won a sex.com
case in the 90s! He didn't get OJ off in the 90s. I say sue them for defamation, and all the other things you can think of (plus what I listed above) and sue for a nice 6 figure PLUS the rights to the domain (since a good portion of your intellectual property resides there) and then... when you win, take down the site and on the front page put the pterodactyl.