How do you secure your bicycle?

I have just gotten back to riding after a decade long hiatus. I ride to get to/fro work right now, but would like to start riding to do errands, the movie theatre, etc. I remember hearing about the Kryptonite gaffe, and wonder if it’s too late to get my old U-lock replaced. As an alternative, I would like to know what other flutherites use to secure their bikes.