Friend with Playstation 2, enjoys this arcade game, and wishes to replicate the experience at home.

Googling on the obvious search terms results in 3D first-person-shooter games that do not involve a lightgun and are motion-sickness-inducing for this person.

Does anyone make a lightgun railshooter with a paintball theme for the PS2?

Since there is a very finite number of light-gun games for the PS2, you should be able to look at each of them. There's a notionally complete list on Wikipedia: List of light gun games#Sony PlayStation 2. The PS1 games should work, too.

That said, none of them appear to be railers, much less paintball-themed railers.

Edit: I take it back. Some of them are railers, but none are paintball.

Awesome. Precisely the information I was looking for. Thanks, Bitt.

Wikipedia also has this handy list of rail shooters. Cross referencing those two lists look to reveal several rail shooters with light gun support.

I have a PS2 light gun that my brother left here many years ago. I have no idea what game it is for. See attached. Let me know if you want it.

Loren, that's awesome. Thank you! I'll check with my friend and see if that particular gun would be useful. I'll let you know.

The extra yellow connector is interesting, I wonder if it uses some kind of proprietary detection system that only works with one specific game.

Tom: Thanks for that second list. Awesome.

Reading that article I linked, I believe that your gun is specifically the "GunCon2" mentioned there.

http://en.wikipedia.org/wiki/GunCon_2

Awesome.

Friend is specifically a fan of Area 51, and that paintball game. Seems as though Area 51 was only made as a PS1 game. Do PS1 games run on the PS2? Wonder if it'd be compatible with that gun.

Largely, yes. But I can believe that there might be some that wouldn't work, and things that used uncommon controllers would probably be at the top of that list.

Here's an official list of incompatible games

Excellent, thanks.

Keep in mind that list of unsupported games only applies to Playstation 2s with a model of SCPH-75001. From what I can see, that is some of the slimline PS2s only, due to a change in the chips used onboard. The PS2 will hand control over to the I/O processor when a PS1 game is inserted, as the I/O processor is the same as the PS1 main processor.

Nintendo did the same trick with the Game Boy Advance. They used the older Game Boy Color processor as some minor chip, until a Game Boy game was inserted.