I first came upon this phrase in Harrius Potter et Philosophi Lapis. It was one of the ghosts, I think, dropping a receptaculum purgamentorum over the head of one of the students; a rubbish bin. A receptaculum is ‘a place where things are put or stored’. purgamenta is 'that which is cleaned away, rubbish, filth’. The Roman historian, Titus Livius, referred to the Cloaca Maxima, the massive drain that carried water and worse out of the Roman Forum into the Tiber, as the receptaculum omnium purgamentorum urbis, ‘the receptacle of all the filth of the city’.
The little grey mouse figure, by the way, came with a recent Lego model of a T-16 skyhopper, a nice allusion to Luke's aside to Wedge Antilles, 'I used to bull's-eye womp rats in my T-16 back home. They're not much bigger than two meter.'
This small mouse lives near the bin. Now Pico spends (degit) a few hours chasing the mouse.