Researchers at Japan's National Institute of Advanced Industrial Science and Technology, Mitsubishi, and Tokki Corp have designed a thin-film solar cell disguised as a leaves on a plant. They plan to develop these thin-film solar cells for use in architecture as well as other everyday uses like toys, household items, clothes etc.
Complete article:
http://techon.nikkeibp.co.jp/english/NEWS_EN/20080527/152443/