If social media is too crowded, or too risky, what about…
oil field services?
An interesting trend is that the providers of the technology to find and extract the oil are sharing more value than ever before with the owners of the actual reserves. This trend in balance of power should increasingly move in that direction as the oil companies rely more and more on technology to search and extract oil from harder-to-reach wells, many in remote places. With oil being the largest market out there, even small ticks further in that direction represent enormous market sizes for start-ups.
Here is a nice overview of the opportunity.
takingpitches 