Pretty good one, found here: http://www.digital-recordings.com/hearing-test/www-ht-pro/ht_help_p.html

The reason I took it is partially due to the weather. See, I've been able to open the windows at night because the night air has been pleasant recently. As I was laying down last night, I noticed that when I was on my left side with my left ear in the pillow, I could not hear the crickets, but if I was laying on my right side with my right ear in the pillow, I could hear them. Hmmm...

So the hearing test results showed a noticeable difference between the sensitivity of my left and right ear, with the right ear being a bit weaker. \:\(

Don't take this test if you don't want to know your hearing isn't perfect.