He demonstrated the challenge involved in using the Web to find a solubility coefficient for a common substance. It seems like this should be easy, but it’s not. Sources that are supposedly authoritative sometimes contain conflicting information. The assumptions behind the numbers are not always made explicit. As a result, experiments are done and re-done unnecessarily. UsefulChem, created on a free, hosted, wikispaces wiki in 2005, makes the usually hidden side of lab work accessible to anyone who does a Web search. ONS participants record detailed lab notes in the wiki and post raw experimental data as it is obtained. The wiki records a history of exactly which changes were made, when, and by whom.