"You know how sometimes you find a product or service and just have to evangelize it to everyone you know? Maybe you really like the Braun Oral-B electric toothbrush. You love playing Halo 2 on X-box so you tell everyone how cool it is. This sort of 'viral marketing' is what companies pray for, since it expands outward through the culture at logarithmic rates, and it’s essentially free. And it's also only going to expand.
"In the 'old days,' how many people could you proselytize to with a horse and buggy? Now, if you like something, you can shoot out an e-mail to 20 of your friends with a button push or text an instant message from your cell phone..."
