A few years ago I raised some money by doing an ironman triathlon. The years have passed, the pain forgotten and the pounds put on. Stepping up the foolishness scale, in April I am running the Marathon des Sables. This involves running across a significant amount of the Sahara ( the equivalent of 6 marathons in 5 days) whilst burdened with a backpack of essentials.
I will be covering the charity's costs in sending me, and a bit more besides, so your donations will really be helping Mencap.
Your donations will also be a great motivation during the 2500 miles of training, (which is going well !), and during the event itself.