For what it's worth, in a recent survey of more than 2,000 legal, ethics, and HR professionals, "60 percent of respondents reported that either their employees were not accurately reporting all hours worked, or they didn't know if they were. Additionally, more than 40 percent of respondents were not confident that their employees even knew how to file a wage and hour complaint . . . ." (August 5, 2008 Press Release.)  The catch to this study is that it was conducted by ELT, a company that provides online wage & hour/employment law compliance training.  But while there is at least a bias on the part of ELT, given its line of work, its conclusion is anecdotally supported by the comparatively high percentage of wage & hour class action filings (as against all other types).