Recruiting diverse samples on the Internet is a tough business. Even if one uses probability sampling, one must still think of creative ways of incentivizing response. For example, Knowledge Networks samples uses RDD (one can use ABS) and then entices selected respondents with free Internet access (or money) in exchange for filling out surveys each month.
One can extend that concept in the following manner – there are a variety of places where people must wait or have time to spare, where they also increasingly have their laptops and their cell-phones, for example, the airport, the airplane, the dentist’s office, the DMV, hotel room, etc., and where they look to browse the Internet without paying any money. There are other places where people just want access to the Internet without paying (say cafes). Hence, one way to recruit people for surveys would be to give free temporary Internet access or local coupon(s) in return for filling out survey(s).
One can extend this method to ‘buying’ temporary Internet access to buying any sort of product (e.g. content) or service.