PopCap has teamed up with American Dental Association and they are giving out coupons for Plants vs. Zombies for PC/Mac during the Halloween period. What is great is that you can print these coupons and give them to anyone. Enjoy your Halloween.
But remember, it is from 30th October to 10th November only. I will not bore you with the details. You can read them out yourselves over at the Stop Zombie Mouth site.