The Mona Lisa's enigmatic smile may have beguiled many a viewer but it could not open your computer if the latter was secured by FxGuard Windows Logon facial-recognition software. Developed by biometrics specialist RCG, FxGuard Windows Logon is designed for camera-equipped notebook computers. Users can access their laptops with instant facial verification before login; no passwords are needed. The software's accuracy is not affected by changes in a user's facial expressions, hairstyle or glasses, or environmental conditions. It also records unauthorised login attempts, providing a higher level of protection. The latest consumer edition release is FxGuard Windows Logon 4.0, for notebook computers running the Windows Vista operating system. It will cost about HK$600 and include a Web camera upon its release next month. Version 2.2 for Windows XP- and Windows 2000-based laptops is available now, priced at HK$380 with a web camera.