Visual metaphors describe cognitive processes in every part of life and function as a connection between what we see and what we think. Mental activities and perceptional interactions of the real world are often interdependent and occur mutually. Cognition is enhanced by the use of the real world, in particular the use of cognitive artifacts or physical inventions (S. K. Card, et al., 1999). We describe the process from perception to information, explain different models of mental representations, and introduce Chi's visualization process. We use these theories and models to introduce and evaluate different visualization tools, which are positioned to explore and navigate a groupware-based organizational memory that is presented as a small case. We point out how the different characteristics and functionalities of these visualization tools contribute to a synergetic match of visual metaphors and cognitive processes.