That lets you do things like freeze time to hold blocks in place that can be used as platforms, or run a few different versions of yourself around a map, Braid-style. The last room in the demo shows the player recording just a moment, moving away from that point, and then playing it back quickly, warping the player past a dangerous barrier.
It's smart stuff, though obviously this is just a concept of a work in progress, and not actually a commercial game yet. Still, we've seen great games come from humble beginnings before -- could this be another Portal in the making?
