The End of Dangerous Science?

This clip from WIRED Science laments the decline of "dangerous" science toys and experiences for kids. They visit the Chemical Heritage Foundation (with its own historical collection of chemistry sets!) to show how wimpy science toys have become. Case in point: a "Chemistry Set" with NO chemicals!

Perhaps toymakers fear of liability lawsuits has helped contribute to the 60% decrease in chemistry graduates since the 1960s.

Of course, science museum exhibits are often just as guilty of the "wimpiness" factor. Safety first (or second, or third) of course, but are there ways to let visitors get involved in experiences that are a little messy and/or risky? That is, more like real science?

Do you have any good (or bad) examples of messy/risky/dangerous science exhibits to share? Let us know in the Comments section!