It’s any email you receive that isn’t spam, but isn’t exactly a personal message either.I would think of Bacn as all those weekly e-newsletters you had to subscribe to in order to gain membership to some lousy site. Now your stuck receiving email that is not really junk, not really spam, but not really email from say... your mom.
Bacn would be a: newsletter, a bill, email you want but it's not that important, or the joke forwarded 30 times around the office.