I have an internal safe room in my garage thats also locked, and plan to install ground ancors, i don't even like giving the wife the key.
Bike thieves are scum i have lost a few bikes to them over the years. The other week someone mentioned that they had seen some blokes looking at the bikes at the train station where i park my 97 rockhopper communter. It only cost £110 but its locked up with an Oxford products motor bike lock, a Kryptonite New York D lock and a Kryptonite forgetaboutit chain and mini D lock, total value of the locks is £200.
I think bike thieves target you, they follow you home so they know where you live and come back for your pride and joy, or get your address from crooked bike shops. When i lived in Sheffield lots of bikes got nicked just after they had been bought from a local shop, too many in my mind for it to be coincidence, my Patriot was one of them :-(
All bike thieves should die a grim death, try digging a mote around your shed and filling it with crocs or get one of those food boxes big enough for a bike they use in the states to stop bears eating your supplies