drive a cactus up your arse for all I care

(Synchromesh gearbox, overhead cam, Tue 2 Dec 2014, 14:46, archived)

well you've embarrassed yourself a little here
quite apart from the fact that I don't have a cactus, I can't see a practical way of driving one up my arse and even if I could surely that would, at the very least, hurt, or even cause lasting damage to a crucial part of my anatomy
( tangledupinblue hairy badge with moving eyes, Tue 2 Dec 2014, 14:50, archived)

tl;dr

( tangledupinblue hairy badge with moving eyes, Tue 2 Dec 2014, 14:50, archived)