There out be many but I think the education/lifestyles/luxury are few sectors which are not over saturated yet.
A lot of people seem to be asking this same question. If anyone has some insights and are interested in co-developing NicheInsider.com, send me a pm
Here is my personal method to find niches : go to BST Section ( sites section ) look for the type of the sites are being sold . these are the best niches now .
hah that actually might work! I think a revolutionized social outlet will still be in demand, a lot like myspace, facebook, youtube, or twitter. A unique twist can do a lot
People would not give you such secrets, but they will give broad terms like health, personal development and make money niches are always good. That is if you do your research and find long tail keywords with low competition.
good point, though sites are very often sold to people that have no idea about what they bought and why they did it And sites are very often on sale simply because they have been making good money for a while and this specific niche is not that "lucrative" any longer... But I like your way, it's one more way to go!