An increasing number of web sites include in their pages subliminal messages, which flash on the screen only for a single monitor cycle, and are consciously perceived only as a slightly irritating flicker. It has been shown, however, that such messages do register unconsciously, and therefore may influence subsequent decisions. The contents of subliminal messages found on the web range from relatively harmless advertisements (e.g., for a certain fast food chain), to political and religious indoctrination. We offer patches for the most common browsers, which will prevent a change of screen content just for a single frame. Moreover, an alarm will be sounded at every attempt to send a subliminal message.