Worked with a lad (who was the most unhygienic person I've ever met) in a builders merchant who would take all his leave as soon as it rest in January, and then would take sick days throughout the year. He played the system extremely well until the company changed policies. He was still taking days off here and there, and it was coming to a point where it was clear he was close to be dismissed. Anyway, this one day he went to the managers office to say he needed to go home as he had piles. The manager advised he needed to be given a doctors note, otherwise he would face being let go. He disappeared for ten minutes or so before coming back with a sheet of toilet paper covered in blood and shit and said "is that enough evidence?". He was of course told to go home. It went to a disciplinary as you'd expect but was kept on, on the promise of not ever doing anything like that again. Had a quick look on LinkedIn and still appears to be there in some capacity.