In 2001, featured a number of articles that generated tons of reader e-mail, both positive and negative. The "Penny Per Page" article brought in hundreds of e-mail messages, as well as over 700 comments on the day it appeared on "Evolution" inspired hundreds of posts in the forums in addition to a steady slew of e-mail that has yet to slow down!

Here are the 10 articles that generated the most reader mail in 2001. Decide for yourself whether they're right on or way off -- and then voice your opinion in the Forums!

Theories of evolution abound, and it's a subject of heated debate. Check out the ideas surrounding the evolution of life!

With one billion Muslims across the globe, Islam is the second largest religion in the world. Learn about the basic tenets and practices of Islam.

Lethal injection is not a light topic, but it's the center of ongoing debate. Learn about the procedures of this form of capital punishment.

The process of picking a lock is actually very simple, but it takes a lot of practice. Explore the technology of locks and keys!

The invention of the machine gun forever changed the way we wage war. Find out what goes on inside these self-loading weapons.

Marijuana is the most-used illicit drug in the United States. Learn the facts about marijuana and how it affects the mind and body.

E-mail hoaxes claim that he foresaw the events of September 11. Learn who Nostradamus was and what he really wrote.

Record numbers of Americans are illegally obtaining the prescription drug OxyContin. Find out what makes this pain killer so powerful.

What would our world be like without the World Wide Web? Let's not find out. Learn how the penny-per-page revenue model might work.

Sex plays a major role in much of our culture. Yet many people are confused about what sex actually is. Explore the biology of sex.