My manager forwarded this interesting game from a japanese site Flash Fabrica, which seems to be reasonably able to tell the age of your brain. If you don't feel as old as you may be, try this.
1. Click 'Start'
2. Wait for the countdown to complete - 3, 2, 1 ...
3. A bunch of numbers will very briefly appear on your screen and then get hidden by circles.
4. Click on the circles to go from the smallest number to the highest.
(The video below requires Flash player and is compatible with browsers Firefox, IE7 or Safari.)
It's also available here.
First time, my brain got 2 years less than my true age . Then kept fiddling with it I got tired and my brain got older. Tried it again after a break and I got 22, 10 less than my first time! Good to know that the brain's age can be adjusted to suit personal satisfaction.
Feel free to enter your scores in the comments and whether you think this is an accurate test.