Steve's just told me about Epic Games offering games for free for a day and he said that Rollercoaster Tycoon (one of my favourite computer games, alongside Theme Hospital and The Sims) is free today, so I've just signed up for a free account and installed it. I'm thinking I'll use it as a reward for finishing NaNo so that instead of eating my weight in chocolate, I will spend the rest of the day every day until the Sunday playing it as my reward.
I recommend that you create a system restore point and close down all your other computer programmes before you install the game launcher in case something goes wrong... it didn't go wrong for me, but my arrow pointer thingy worked very very slowly and it messed up the order of the icons in my task bar as well as having to reboot which was slower than normal too. It's done and dusted now though, so I can concentrate on preparing for NaNo then use it as my completion reward instead of the chocolate. I'm still gonna have a reward of a J2O for every 5k words I write in a single day, so that I will, in theory, be finished on or hopefully before the 10th. It's one less thing to have to find the money for though.