So, it's possible to actually set the camera position to a different object (as seen in Aquanauts).

So can we have a gun that you shoot at object, have a variable set to it and when we press a certain button on the keyboard, have the camera move to that object?

I'd like to see that, please, pretty please.

Also: Can this be applied to other actors that sharpaim?

Anyway, thanks.

It's not a variable - it's a Lua script.
What you described is pretty easily possible, but also incredibly vague in what you are asking for.

He (or she) asked if it was possible to shoot something, press a button on the keyboard, and have the camera move towards the bullet(s?).

Yes, that's possible, though while in-game it's actually based on switching to Invisible actors.

You might want to check out the Crobotech beta; more specifically, the crobo tank. It features pretty much exactly what you want on a non-line of sight mortar crab tank thing.

This might also apply to the Guided Missile Launcher that CaveCricket released and subsequently took down.

The way it worked was after the missile was fired, you pressed the right mouse button and it would switch to the missile, which was an actor itself.