Thanks to the dumping of an old law that prohibits commercial messages on currency of any kind, including stamps, the United States Postal Service aims to boost its bottom line - if not its reputation amongst philatelists - by accepting company or brand logos on postage stamps.

Although a certain degree of stamp customization has been permitted since 2004 - featuring choices as bizarre as the mob-related former union boss Jimmy Hoffa - this is the first time companies have been able to feature a brand message.

First off the mark is Hewlett-Packard, with a range of stamps that will feature photographs of founders Bill Hewlett and Dave Packard, the garage in which they launched their company, the HP logo and a current print ad.

HP executives and sales-force members are already using them in mailings, says vp-brand marketing Gary Elliott, although the company is working on other potential uses.

The ceding of a former no-go area is driven by the USPS' need to stem a loss of income as consumers and businesses increasingly move toward email. First-class mailings have plunged from almost 55 billion pieces mailed in 1998 to just over 43bn last year.

But there could be a downside - consumer opposition. Jim Nail, cmo of media and marketing consultant Cymfony predicts: "There has to be a backlash of some sort. Here it is, this sacrosanct space where we've never seen ads before."

However, he believes the backlash will not result in lost sales, but rather a psychological hardening of resolve against the overall pervasiveness of advertising.

But even if there is public outrage it is likely to be temporary, argues independent branding consultant and author Joe Calloway.

"If there is a negative reaction, I think it will be along the same lines as the way some people reacted when baseball and football stadiums began selling corporate naming rights. There was a great outcry, but then, for better or worse, it wore off and we all became used to it."

Data sourced from AdAge (USA); additional content by WARC staff