What's missing? No doubt you've noticed that Julie Bort's list does not include one of the most popular extensions, an ad blocker. Believe it or not, Google does offer ad blockers and flash animation blockers. It also offers extensions that block ads from specific sites, like Facebook. So why didn't any make it to the list? Bort says, "Although ads can be annoying, magazines and newspapers are hurt by ad blockers. Given the state of newspapers during these economic times, and the fact that I earn my living from that advertising supported medium, I don't use them and couldn't bring myself to recommend any." Are there any other favorite extensions you'd like to see on the list?