So you think you can tell Arial from Helvetica? Try this logo-quiz and see.

I don't know how I missed this, but our fave typenerd blog ironic Sans has created the ultimate Quiz to torture ad-assistants, our copywriters, and that clients cousin who has a computer and thus is a designer with: So you think you can tell Arial from Helvetica?. He has simply taken famous Helvetica logotypes and re-done them in Arial - then asks you to select which one is the original.
This would have been a lot more difficult if it were a bunch of Arial vs Helvetica logos, but I can honestly not think of a single logo based on Arial so I guess that's why he didn't go there. As you can see, I scored 20/20. No pressure. (Hint; t's, r's and i's are the window to the soul of a font - a's and o's are also a dead giveaway.)