i love the tour de france. even though i haven't hopped on a bicycle since the sixth grade, the idea of a bike tour is very alluring once you cast aside the physical demands and the achy body sure to result after a long bike ride. if you have no aspirations to be the next ironman, then check out the folks at kona coast cycling tours where they make such an adventure seem not only possible but lots of fun to boot.
the old mamalahoa hwy tour which meanders through my favorite part of the big island would be my pick, however java addicts would probably savor the kona coffee express tour which includes a stop at a local coffee farm. an added bonus is that if you get bonked or, let's say, are mortified when the grammar school set initiates a breakaway, you can cruise in the team car tour van, and enjoy the four wheeled ride until you're ready to join the group again.
{update | dec 2009: kona coast cycling tours seems to be no more and has handed over the website domain to their friends at orchid isle bicycling. this means, alas, the rides mentioned above are no longer available but circle island bike tours are now offered.}