Good natured (?criminal) activity, e.g if you are at a festival, you good-naturedly remove the "Rubbish Point" sign from near the garbage point and then place it proximate to the tent / caravan of the person(s) you wish to get into a bit of a bate. There's no particular malice involved, but if Hunter Thompson was doing it then it might look as if there were. A hoogler is one who commits the hooglery, the hoogled is he / she / parsnip who is the victim of the hooglery.
A co-worker wasn't best pleased about having his default MSN avatar replaced with a picture of Dale Winton. He suspected HOOGLERY had occurred.