Online listening test?

[superspiffy]

Is there a site or a program somewhere that gives you a full frequency test? I want to know up to what frequency can I still hear. And even which of my ears is better or worse. This might help me on deciding whether I should start converting stuff to a higher bitrate or even lossless and whether I should even buy expensive earphones.

[contoursvt]

I use this tone generator software and it works great. I use the windows version but there is an OSX version too. Just download the lite or free version. Good enough :)
http://www.nch.com.au/tonegen/index.html

[pungohboy]

I have tried http://www.ninjaringtones.com/ Dont know if it is what you want though.