Here is a link. Read up!
Delphi Multec 3.5 Heated Tip Port Fuel Injector
Seems it's intended for flex fuel and it doesn't say if it improves combustion for straight gas. At 500*C it ought to though. Smokey would be proud.
This could be an interesting mod once these start showing up in wrecking yards. The next question will likely be what engine changes will take the most advantage of these, like ignition timing, cam timing, compression ratio, intake air temp, etc.