Clayton Cramer, a software engineer by day, and an amateur historian in his "too much time", singlehandedly lead a crusade debunking the lies of "Arming America."
The passengers of United Flight 93 did what our government could not, stop a hijacked airliner from crashing into a national landmark.
Just look at FR itself if you need more examples of people doing great work with "too much free time." Freeper RLK, a physicist by training, provides some of the most insightful, far-looking political analysis anywhere, and he mixes it with humor, reason, and solid psychological insight. Freeper JohnHuang2's essays typically say more in a few paragraphs than the editorial pages of most U.S. papers.
The "blogosphere" is full of such people, commentators from all walks of life offering better, and more, daily fodder than most newspaper columnists.
I for one am glad that so many people have "too much time on their hands." Our lives are better because of their passion and because of their constructive use of their non-job hours every day.