Here is a 2-minute video clip, from 2007 or earlier, in which a British army lad is "sentenced" by his mates to a slippering "for breaking the Queen's rules" (we are not told which ones).
He draws a card from a pack to determine how many strokes he is going to get. He is in luck -- he picks a 3.
Each of the three strokes is delivered by a different colleague as the culprit bends over the table with his shorts pulled down and his feet apart. Apparently this is known as "getting reefed" and the punishment is called "a reefing".
Of course this is all in jest, and the atmosphere raucous; but the whacking is real, and the lad takes his punishment like a man, with dignity and without complaint. His backside is red and smarting at the end.
What is interesting is that, even though these fellows would hardly have been born when CP disappeared from mainstream schools, the idea of CP as a formal ceremony, with the offender bending over a desk for a stated number of strokes across the buttocks, evidently comes quite naturally to them. Could it be hardwired into the Englishman's DNA?
Note also how this faintly echoes the 19th-century practice of "cobbing" in the British army, when a man would be unofficially spanked by his colleagues, without reference to the military hierarchy, for breaching their own code of honour.
HERE IS THE CLIP: