Some rather bright German researchers have been perfecting the printable battery and figure to be on course for a 2010 release.  Using a silk screening process they impregnate paper with many hair thin layers of zinc to form an anode and manganese for the cathode. At peak it can produce 1.5V from a total of 1g the two metals in a thickness of about 1mm.  The charge dissipates over time, so that audio greeting card your kid gets will eventually run out.  Drop by Slashdot for the particulars.

“Paper-thin batteries that can be printed onto greeting cards or other flexible substrates have been demonstrated at Fraunhofer Research Institution for Electronic Nano Systems in Germany. The batteries have a relatively short life span, as the anode and cathode materials dissipate over time. However, they contain no hazardous materials.”

Here is some more Tech News from around the web:

Tech Talk