A lot of search engine traffic now comes from mobile phones and unlike the computer audience, those visitors from mobile phones cannot really be optimally targeted with Adsense ads given the space constraint. The issue is yet to be sorted out for the English speaking audience. However, Google appears to have figured out a way for at least the audience from South East Asia like Japan, Korea and also China.
In a recent patent application filed with the USPTO, Google has described the use of the vertical text format; something that is pretty common in these Asian scripts to save on ad space and also present a more optimal way of displaying ads. This is what the inventors have to say,
“A technique, method, apparatus, computer program product, and system are described for vertically displaying text of content items on small display devices. In some implementations, individual characters (e.g., Chinese, Japanese or Korean characters) of text can be displayed vertically in one or more left-hand or right-hand columns of a display. Text strings (e.g., Latin characters, a URL included in the text) can be converted to one or more images, and the images can be rotated for display in a column”
This is not exactly revolutionary, but it can be an effective way to monetize the mobile traffic from these high density regions.