Boards
Grandmothers tagging themselves in FB as Grandmaster Flash
It almost seems legit. It probably is fairly legit and amusing.
But worth remembering that if you're 60 now (a kind of median age for a granny, I reckon) you were 28 when The Message came out, so maybe there's a bunch of them who go with it because they're pretty fucking cool.
https://twitter.com/blinkboxMusic/status/510383137139228672
(There's also a Buzzfeed article about it but I'm going with solid gold Tesco evil on this one.)