CDs that once I start to listen to them outside, I often find impossible to turn off (even if it means several more hours in the pub than intended):

The Harder They Come - soundtrack
Paris Hilton - Paris
Blondie - Plastic Letters
Blondie - Blondie
Bauhaus - Crackle
Rachel Stamp - Oceans Of Venus
Garbage - Garbage
Sisters Of Mercy - A Slight Case Of Overbombing
The Ruts - Something That I Said: The Best Of
The Bangles - The Best Of
X - Los Angeles
Nuggets - various artists