After having a good alarm and tracker, what are good security devices, like a steering wheel lock.

I once saw an inexpesive item (maybe round the gear lever??) and thought what a good idea, but have now forgot what it was.

 

Had a multi-lock gear lever lock on a previous car a few years ago, put the car into reverse and slide a u clamp into the housing, very effective usually, but the car can still be towed away!
Also a good thing as the fitted price is about £175, if you change cars take the housing and clamp off before you sell and then you'll just need to buy a new bracket which welds to the transmision tunnel for the new car - approx £30