The Poincare conjecture

Over the weekend I read "the Poicare conjecture" by Donal O'Shea. This was a book about the recent proving of the Poincare conjecture. It claimed to have some history about the reclusive Grigori Perelman who recently proved it, however there was little detail about Perelman at all (that is what reclusive means). The did a good job of explaining the history and background to the Poincare conjecture. I was feeling that I should have some idea about what this conjecture is about. What thing I never thought about was that if you continued forever on a journey you would eventually return to your starting point. Perhaps there is some subtle topological strangeness in the Universe. Given that nothing can go faster than the speed of light, this is a totally impractical insight. Such is the use of topology.