I've had all sorts of attempts at making money. However, it took sites a couple years to start getting traffic (+100 visits a day), and by the time I realized I was making money, my "sites" (they had content, but all pages had been converted into Allclicks.com Enter links.), the free hosts shut them down, or the free hosts got shut down.
But, I realized, that it takes a lot of work to make money. Just think of all the people trying to do the same thing. I myself have a few things in the works, buy as Gayo said, I get bored, then leave them for a while, and pick them up 6 months later, and start over.
If there was a way to easily make money, that means there are people doing it. By the time you hop on a trend, you are going downhill.
What you have to do is start your own trend. Make something new on the net. Something interesting, something people will want to go to. Don't depend on search engine traffic. You want people sending emails to all their contacts about your site.