Mobile sites?
Google put out a report a little while ago showing almost 50% of their traffic came from a mobile device... 2013 will surpass 50%
I buy shit all the time on my iPhone and iPad. There are a ton of providers and even FREE solutions out there to make mobile sites.
I started pushing mobile in adult years ago, back when no one thought it was making money and was an EASY $2k to $3k a month from my small affiliate sites.