I think any money related keywords pay well........ insurance, life insurance, car insurance, credit cards, mortgages, re-mortgages etc.... Trouble is, competition will be high.
the classics: money, health and finance. It is true too I ran a gaming blog and a personal finance blog. Even though the gaming blog got more traffic 5x (I spent more time on that one) I still ended up making 10x more profit from the finance blog.
I don't think someone will share his top paying keywords. Niche at most And yes the web hosting niche is performing well for me.
people say something about medical and lawyer or any high fee service will give you more paying. but i never tried those keywords.