A very general answer would be mobile services. Not ringtones, but mobile services like texting services, etc. They are still pretty small now, but those jokes via mobile or the dating on the phone stuff will be fucking huge. Most phones now come with mp3 compatibility so ringtones are a thing of the past, not to mention ringtones will be losing their groud really soon as there is far too much fraud, and the government should be cracking down on it really soon.
Another huge emerging market, which is actually somewhat of a sleeping giant is the UK market via affiliate marketing. It's been around for many years, but nowhere near the peak it can potentially hit over the next 2 years or less. Sure, we prefer to be paid in USD, but buyers in the UK are everywhere and they, like us, like to spend lots of cash on really stupid things. So the overall potential in so many markets is just unfathomable. You'll start seeing and hearing more people talk about it over the next year or so as it develops more and more, but this is DEFINITELY something to look out for or to get into asap before the boom happens.
