I'm currently seeing pleasing results promoting Channel 4's 4oD via TradeDoubler. 4oD is a free TV catch up service, allowing users to watch programmes from the Channel 4 archives. It's very useful for watching shows you missed, it's free and best of all, Channel 4 will pay you a pound for each user that downloads it. Seriously, does affiliate marketing get any easier than that: you have a great product, available for free and it's something users will want when they know about it or might be looking for anyway.Similarly, Firefox via Adsense Referrals. Firefox is a great app. Chances are that you'd recommend it for free anyway, but Mozilla/Google are willing to give you up to a dollar for each person that downloads it. Some people have to go door to door trying to flog things to people who...