caffeinemessiah writes "The BBC reports that researchers at UIUC and the University of Amsterdam, Holland have used "emotion recognition" software to determine Mona Lisa's true emotions. The algorithm is based on a library of neutral face images of young women and determined that Mona Lisa was 83% happy and 9% disgusted." From the article: "The program, developed with researchers at the University of Illinois, US, draws on a database of young female faces to derive an average 'neutral' expression. The software uses this average expression as the standard for comparisons. The New Scientist says that software capable of recognising emotions just by looking at photographs could lead to PCs that adjust their response depending on the user's mood. "