DyPERS, 'Dynamic Personal Enhanced Reality System', is a wearable system which uses augmented reality and computer vision to autonomously retrieve 'media memories' based on associations with real objects the user encounters. These are evoked as audio and video clips taken by the user and overlayed on top of real objects the user looks at. The user's visual and auditory scene is stored in real-time by the system (upon request) and is then associated (by user input) with a snap shot of a visual object. The object acts as a key which is detected by a real-time vision system when it is in view, triggering DyPERS to playback the appropriate audio-visual sequence. The vision system is a probabilistic algorithm which is capable of discriminating between hundreds of everyday objects under varying viewing conditions (lighting, pose, etc.). The record-and-associate paradigm of the system has many potential applications. Results on the use of the system in a museum tour scenario are described.