For some, the road to discovery is a four-lane highway lined with sign-posts warning what lies ahead. For Peter Agre, the Johns Hopkins University researcher who accepted the 2003 Nobel Prize for chemistry last month, it was more like "driving out on a gravel road in a remote part of western Maryland and suddenly coming to a large city" – hard to miss and yet completely unexpected. Since Agre and his group cloned aquaporin 1 (AQP1) in 1992, hundreds of these previously unknown channels have been discovered in plants, animals, and lower organisms; researchers have made progress toward understanding their structure and mechanism, and how faulty regulation can lead to disease. Yet, as with many other proteins, a trickle of information soon turns into a downpour as it becomes apparent that functions may be much more diverse than originally anticipated.