Looking to increase ad revenue and keep more of that money for themselves, a number of major media publishers are set to begin using a product called Publisher Media Exchange from Right Media to auction off ad space on older news pages. Fox Interactive, Tribune Co. and others such as Six Apart, the maker of blogging platforms such as MovableType and Typepad, are using the system to auction off space on non-premium pages. The shift to an auction platform for such sales gives buyers the flexibility to make purchases on the fly and change them when needed and is meant to play off the success Google, Yahoo and other networks have enjoyed with their ad-buying-through-auction methods.