My preferred daily ran an entire feature on extending that 5-2 diet that I myself have been using on and off. The suggestion is that the five days of carrying on as normal interspersed by two days of abstinence or, in some cases, a change of behaviour, may be extended into other wide ranging areas of life. Alcohol detox, relationship fixing and even worrying are all considered, the latter by Jon Ronson who is the absolute king of angst. Follow the link for some entertaining and thought provoking reading.
My favourite ideas has got to be the 5:2 spending plan. What a wonderful way of kicking start thrifty habits and fostering money saving habits for those who don't usually give a thought to their daily spending. To my impoverished student friend who can't resist the urge of shop bought lunches with bottled drinks, BOUGHT FROM THE RAILWAY STATION FOR GOODNESS SAKE, listen up! It might be a jolly good idea for you. You know who you are! For us more accomplished thrifters and frugalistas, perhaps we might set ourselves an altogether harder challenge. How about reversing the digits and keeping to a 2:5 regime?