Turbine engines?

[humpbackmaniac]

Ok this has been bugging me due to limited spanner knowledge. How does one take the drive from a "jet" engine, I am talking about helicopters etc, taken that the power is from the central shaft, but how then do you take the drive shaft out of the exhaust? direct the gas away and take the driveshaft through a port in the side?

Recently saw an XJS with a Turbine engine fitted and although blatently daft was intreguing. (spelt wrong I think)