Name That Redhead: Amy or Isla?

Name that copperhead.

One of these adorable ingenues is Isla Fisher, the overzealous bridesmaid who snares Vince Vaughn in "The Wedding Crashers" and the title character in "Confessions of a Shopaholic," opening today.

The other is Amy Adams, the fairytale princess who falls down a well and comes up a manhole in "Enchanted," who gets romanced by Ryan Reynolds in "Definitely, Maybe" and plays the novice in "Doubt."

I've confused the two ever since I saw "Talladega Nights" and thought the cute redhead was Fisher and then the credits i.d.'ed her as Adams.

This is how to tell them apart: Adams (on the left) is wide-eyed and demure, Fisher (on the right) wild-eyed and unstable in a Lucille Ball way.

They both make me laugh. You? Other actors you confuse?