One way is to look at the technology coming out of the lab and figuring out what to do with it. The second way is to take a close look at what users and businesses want, and figure out how technology can deliver it. Since I am not a technologist (although I do have a technical degree), I usually use the second method to look for new markets.
However, as a great posting at the Venture Capital blog Due Diligence pointed out: The Next Big Thing sneaks up from behind while you're trying to do your work, kicks your ass, walks over you, and either rifles your pockets or drops gold into your hands. If it's gold, they write a story about it one day. The others you never hear about, unless you live here and know them personally . As they say, Go Read the Whole Thing.
Keeping that theme in mind - that the Next Big Thing really isn't predictable - here are a few of many trends I am currently looking at anyway:
1. Demographics - The U.S. will soon experience a large increase in the older population, creating more demand for healthcare and nursing facilities. Two areas that might benefit are medical delivery systems and robotics, which are already being tested in nursing and elder-care environments.
2. Entertainment - Entertainment consumption is going nowhere but up, and how entertainment is delivered is one area I am looking at, such as wireless connections between the TV and PC, and how users control and interact with their entertainment (3D control systems that use MEMS gyroscopes, for example). I also throw gambling into the entertainment mix, and that is another area where our children will do it in ways we never imagined (such as gambling via cellphone).
3. Security & Safety - The 9-11 disaster and aftermath has already produced a flurry in funding for security technologies, although this area is probably over-subscribed by venture capitalists at this time. This area ranges from biometrics - identifying people on anything from fingerprints to DNA to face recognition - to secure printing technologies for passports.
4. Supply-Chain Control - Following leaders such as Dell and Wal-Mart, U.S. companies are looking for ways to closely link and monitor their supply chain, which is one of the largest drivers of Radio Frequency Identification (RFID) technology today. I could write pages on what is going on in RFID, its implementation, and those that oppose it, but suffice to say that this is a technology that will be everywhere in 10 years, replacing the bar codes on all the items at the grocery store, tracking your luggage through airports, and tracking packages through our private and public delivery systems.
Those are the "high level" trends. Then there are industry specific trends, such as the write-up I did about the car, which is changing from a mechanical system to an electrical system, and other industry specific areas which are driving emerging markets.
These are only just a few - there are a lot of other demographic, societal and industry specific trends driving emerging products that I don't cover - I just look at those areas where my company has a core competency, giving me a market scope which is digestible. Otherwise I could spend years analyzing all sorts of trends, just to see the Next Big Thing pass me by.