Google now running ads on mobile search results for people who use a full HTML browser (Android, iPhone, Opera, MicroB etc) to do their mobile searching.

There's a screenshot over at IntoMobile:
http://www.intomobile.com/2008/12/08/google-bringing-adwords-to-mobile-browsers-iphone-and-g1-get-adwords.html

http://adwords.blogspot.com/2008/12/extending-your-adwords-campaigns-to-g1.html

http://googlemobile.blogspot.com/2008/12/new-adwords-options-for-iphone-and-g1.html

http://www.youtube.com/watch?v=q4R-wF6sdDg

http://searchengineland.com/adwords-new-mobile-targeting-15751.php