Imagine a semantic web search tool, something like Google with iTunes. Now stop to imagine and go read about mSpace.

mSpace is an interaction model to help explore relationships in information.
mSpace helps people build knowledge from exploring those relationships. mSpace does this by offering several powerful tools for organizing an information space to suit a person's interest: slicing, sorting, swapping, infoViews and preview cues.
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An mSpace presents several associated categories from an information space, and then lets users manipulate how many of these categories are presented and how they're arranged. In this way, people can organize the information to suit their interests, while concurrently having available to them multiple other complementary paths through that information.

Don't forget to watch the demonstration of how mSpace works.(via Slashdot)