Scythe Kama Meter
 

The Scythe Karma Meter is a drive bay device to monitor the temperature inside your case with 4 separate diodes, control the fan speed of up to four fans and set the master volume of the PC. The Kama Meter shines with perfect build quality as well as 8 different back light modes. We take a close look to see if its features are useful and temperatures are accurate.

http://www.techpowerup.com/reviews/Scythe/KamaMeter