Digimarc Corp. (DMRC)

The company owns patents for embedding watermarks in digital media. Their software has long been bundled with Photoshop and Corel Paint.
They market a service that will monitor the use of a copyrighted image on the internet. Reviews by photographers claim the service is expensive and ineffective. (If you copy the document enough times you can eliminate the watermark) More interesting Microsoft has partnered with the company to put digital watermarks on satellite images on their map site, and the DOD has signed two contracts for document security. They have interesting technology that would allow you to take a picture of a printed picture, with a cell phone say, and then read the encrypted watermark. In packaging this would allow invisible anti-counterfeiting codes, it would allow cell-phones to link to print ads.
On the down side, revenue is on the order of $18 million per year, 80% of that with two unnamed customers. For all the possibilities of the technology, they don't get paid very much. They claim that revenues are down because with sales in the software industry down, patent royalties are down as well.