A detailed letter that accompanies a Christmas card. The sole purpose of the note is to boast about the sender's family. Usually plagued with unnecessary exclamation marks and unwanted particulars about said family, the boast-it note is the bane of the festive season post.
Mrs B: You ok honey?
Mr B: Damn no! Just read Gina's card . Her kids are both crackwhores and somehow still child prodigies apparently...I just...don't...get it...why???? *breaks down in tears*
Mrs B: Don't take it seriously darling. It's just her annual boast-it note.
A Post-it note that has something along the lines of "I rulez" written on it, and then stuck on some twats back
"I'm a chav" (Most chavs boast about that fact"
'Ere mate, yoo got a boast-it note on your ass'