I second that. His movies all have that "rewatchability" qoutient. The Sherlock Holmes movies I can watch over and over and over. Lock, Stock and Two Smoking Barrels is a comedic masterpiece. He was often compared to Tarantino when he first came on the scene but for me he's far more talented a filmmaker. While his movies have a distinctive comedic quality about them that permeates through virtually every scene and everyone in the cast, Tarantino's seem to be a forced effort to be clever and important, often failing at both.
My list (there are so many that I likely left out!):
Bladerunner
Day of the Jackal
Kiss Kiss Bang Bang
Guy Ritchie's Sherlock Holmes movies
Lock, Stock and Two Smoking Barrels
The Incredibles
The Godfather 1 & 2
Dr. Strangelove
2001
The Bourne Trilogy
Bullitt
North by Northwest
Raising Arizona
The Big Lebowski
Elf
The Maltese Falcon
Casablanca
The Big Sleep
To Catch A Thief
I have to stop here. I may add more later.