The highest paying keywords are the industries with the biggest profit margins. These industries are the ones who are able to bid such high amounts per click.
One industry that springs to mind is "finance". But remember, going for the highest paying keywords isn't always the best idea as you will have stiff competition. A lot of people are trying to do exactly the same thing.
My advice would be to choose an area that is as untouched as popular, become the best at it and you will get the rewards you're after. 
__________________
Bannaz™ - Flash Banner Design
Leading designers in online advertising
www.bannaz.com
|