Here's a wierd one.
Vacuum sputtering. Basically, you put whatever you want coated in a vacuum chamber, and in that chamber is an electrode and target. An electron beam is fired at the target (this is no big deal, your TV does it all the time) and part of the target vaporizes and clouds in the chamber. The end result is that your item gets coated in a very very fine layer of whatever material the target is made of.
Now, this wouldn't hold any real advantages over electroplate or other processes for metal parts...
...but vacuum sputtering can coat *plastic*. Chrome glock, anyone? Platinum plated 1911s? a nice nickel Walther P99?