I could use this!
According to a New York Times review (registration required) of some interesting recent patents comes this one that I sure could use on some days:
The most expensive watches are those crafted to tell time precisely. James Logan has won a patent for a timepiece that deliberately runs fast at random intervals during the day. His invention can be a wristwatch, pocket watch, clock or computer clock. It intermittently displays a time of day that is several minutes fast to encourage punctuality. The watch can be set so the person who consults it does not know whether it is fast or not at any given time. This feature can also be used only on days "when promptness is particularly important." Mr. Logan won patent 6,411,568.