One thing I've noticed lately is this increase in the number of sites that offer how to information and guides. They are like article directories in a way, but a bit more specific.
I just found another site that's kind of in that category. It's called YouBundle. The concept is very clear. You bundle together some of your knowledge and expertise.
The very concept immediately suggests ideas. For instance I could bundle together my favourite blogs ... or the funniest comedians in Australia ... or the best cafes in Perth, etc.
It definitely seems to be worth joining and contributing to.