Everybody's doing it

Kottke and waxy today both link to a list of things they consider mainstream yet illegal (now that the Pirate Bay has surpassed 15 million unique peers):
1. pirating media/software
2. alcohol during Prohibition
3. speeding
4. marijuana
5. sodomy

I think the list is more informative if you put them in order of probable number of participants (at their height, for the prohibition one to be fair). I'll give them estimated percentages, even.

100%: Of them all, speeding is the only one that is completely universal. Everyone speeds.
50%+: Next would be sodomy. I would wager significantly more than half of America has committed an act of sodomy at some point.
30%: Drinkers during prohibition. Currently, about 60% of Americans drink. So we'll guess that number is a bit high for early America, and that not every drinker would break the law.
25-30%: 70 million adults over 18 have tried it. That's about 23% of the population, and doesn't include those troublesome highschoolers.
1%: Assuming that ALL of the Pirate Bay users are American, 15 million is an incredibly low number, just 0.05%. That's just Pirate Bay, though. Let's assume all other forms of piracy brings that total up a bit. It still doesn't really fit in with the rest of the group.