RE: little turbos??
First up, a Turbo and a Supercharger do the same thing, but in a different way. They both compress air/fuel to give more power - but a Supercharger is Crank Driven and a Turbo is Exhaust driven - I have never seen an RC Turbo - but there are a few RC Superchargers out there RBInnovations makes one.
As for wether they work ~~ it is one of the most hotly debated subjects on this board.
The big issue people have with SuperChargers is that on a 2 stroke engine the Intake and exhaust port are both open at the same time - so any extra pressure created by the Blower goes straight through the engine - doing nothing.
But of course there are those who claim they have them and that they definately make a difference. (placebo effect?)
People usualy conclude that:
If they work it is probably only a slight increase and that that increase will help low end torque, but have no effect on the top speed (unless you re-gear), you certainly wouldn't see the sort of performance increase you would by supercharging a 4 stroke.
Ultimately it is a case of "get one if you want" - but most people would consider a new engine to be a better investment.