never leave an expensive bike locked up outside...
My bike isn't worth as much but it's worth more than a $1000, so I never lock it up outside in plain site for anyone to see. If they can't steal the whole bike I'm sure they could grab some other expensive component off of it.
It's unfortunate because I can't ride my bike to the store to buy a few things, I used to have a cheaper $200 bike I used for going to the store - but I sold it.