My first jj2 internet games was back in south africa with triple splitscreen (me, distruct and another friend of mine you wouldn't know), it was stupidly fun, we thoought yellow seekers were nuke grenades and such, and thought electroblaster was the best weapon and such.

Anyways, you're talking about LAN, so I'll get on topic, I used to have 2 PCs inmy room back in South Africa, where I played LAN with Distruct and Commander Dats, twas fun, but that was over 3 years ago.

There was a more recent event though...*enters brag mode*
Last year in August at the international JJ2 convention: me, Toxic Bunny and Fquist were playing JJ2 LAN on FQuist's two computers (we tried to get it owrking over the net but couldnt get it right ). Toxic Bunny was on the one PC, and FQuist and me were splitscreen on the other PC (wasn't a problem since I use modified player2 keyboard controls anyway).
We played loads of battle levels from the bash4 collection. It was great fun, yet so biased, the PCs were placed so that TB couldn't see me and frankenquist, yet we could see him easily, he was running around the whole time looking for us while me and quist were constantly battling each other, ahhh the memories, not everyone can say they played JJ2 splitscreen with the great FRANKENQUIST!

Oh, and I have a new respect for people who play jj2 with default keys, you should see quisty's hands move!