Random-ass inventions! (Random ass-inventions)

[Melfice]

Actually, a railgun is very much possible while applying physics.
See, that's where you put a line of magnets and use those to accelerate the projectiles. (Linear accelerator)

They have something on Thinkgeek, so you have your own magnetic accelerator at home!
http://www.thinkgeek.com/geektoys/science/a673/

Watch the video too, and see that railguns aren't that far off.

[Loyal]

...Jesus Doc, calm the feck down. I could go and devote an extra paragraph or two to the principle differences between your thing and their things, but I'd rather not bait you to continue.

[TDK]

Originally Posted by Melfice

Actually, a railgun is very much possible while applying physics.
See, that's where you put a line of magnets and use those to accelerate the projectiles. (Linear accelerator).

She was talking about how railguns already existed and that physics does give us awesome stuff (like railguns).

And that's not how railguns work. The projectile is placed between the two rails, completing the circuit and creating an intense magnetic field which then (along with some other physics stuff I'm not privy to) accelerates the projectile along the rails.

Or maybe you were talking about something else? I'm tired...

[The Artist Formerly Known as Hawk]

No, a linear motor doesn't need anything to complete the circuit, the current running through the rail constantly changes the magnetic polarity within the rail, which pulls the object along.

Wiki has more on the subject.

EDIT; Actually, no, I was wrong. I was thinking of a Coilgun, which is different again. It seems actual Railguns do induce a current through the projectile.