I used to work for a major cinema chain in Manchester who, over the course of just under a year, had underpaid me more than £3,500. I had raised it with my managers several times and I was always batted away, despite having evidence I had been underpaid. This went on for over a year with my issue being ignored. On a whim suggestion I messaged John on Facebook. Within three weeks I had the full £3,500 in my bank account and a written apology from the cinema's CEO.
It probably took John less than 5 minutes to deal with my issue but for me it was a huge deal, I was earning minimum wage and that kind of money is huge. I was genuinely surprised that John listened and did something about it - he's certainly earned my vote for 2016!