Bacn, pronounced 'bacon', is "Notifications you want, but not right now."
Moreover, it's those e-mails you get from sites (such as Twitter, Facebook, Viddler), that you want, but don't really have time for.
Bacn is a step above spam, and a step below personal e-mail.
"Sorry I didn't get back to you! I was catching up on all my bacn."
"Dude, I got so much bacn, today!"
"Sorry I lost your e-mail in all the bacn."