I ran across this quiz today on Ironic Sans: So you think you can tell Arial from Helvetica? Several logos using Helvetica were altered to use Arial. Pretty ingenious test.

I scored 20/20, but Mattell & Toyota were difficult as they are all caps and don't use the tell-tale characters. Of course, it helps that this chart showed up the other day as well.

[via Daring Fireball & swissmiss]