No, really. Cards from the Magic: The Gathering game. So called because, like crack, they are cheap but highly addictive and you never ever stop buying more, even when it's harming your job, your social life, and your health.
The term can be expanded to refer to any collectible card game, but Magic remains both the first and the best of these.
John bought another pack of cardboard crack, even though he just sold his left kidney to pay his rent. I think we need to do an intervention.
A collection of quotes, either from famous people/pop culture or your own personal friends, which is placed on a rotating basis into your signature or profile on online forums, emails, games, communities, etc.
"Ha! That's great! I'll have to put that one in my sigfile."