You've gotta be one hip grandma to be caught rolling one of these ghetto blasters. Created by Classen & Partner, the Mskyo (which stands for Momma Said Knock You Out) is an old-school shopping cart with a built-in speaker and auxiliary jack that lets you blast out your tunes while cruising the aisles at the supermarket. No word on pricing or just how much battery life you can expect from the speaker, but what better way to commemorate grandma's 75th.
Reminds me of when I was bored and made a pair of speakers using a pair of diaper boxes as the enclosures.
They sounded surprisingly good considering.
Those trolley things can handle some weight, so a fair-to-middlin' 12-volt amp and a sealed lead acid battery would give you decent boom for a decent amount of time.
What they need is a piece of matching fabric Velcro-ed over the speaker hole so you can do that whole "Caddyshack" reveal/rocking out thing like Rodney's character did.