We all know that one way to make money is to build a list and mail them and or sell solo ads. It can be a pain to get subscribers in the pace we want. I have used inmobi.com to get mobile traffic for a dead-simple landing page that pass the (5 second test). Create a simple ad and watch the leads ROLL in. I usually pay $0,5 per quality lead in my niche - I know it can be done cheaper - but this works FAST. Just my 2 cents.