Just what the title says. An actor that, when it has thrown a stone, will automatically generate another one.
Or a stone that you can throw, and then get another in your inventory.

I know there's the VED grenade launcher, but it's not got the same feel as launching stones. Also, I don't believe it throws them with the insane velocity that normal stones have.

Similar to the infinite-bomb dropship? I see what you're getting at here... what if you made a stone that when thrown, went a certain distance, gibbed into two stones- one with no velocity, and one with the same velocity as the first- and then picked up the one that fell? Would that be possible with pure-ini?

Just use the infinite bomb script on the stone and tweak it a bit.

Not really, I just slapped on a questionable infinite bomb script from another mod onto a Zombies '09 HE Grenade. ( I then killed everything in sight since the grenade detects that it is thrown, and gives you another, I think it was from Citadel, by weegee )