Does anybody make anything that will monitor, with independent sensors, the temps inside my case?

I have a sneaky feeling that my Ultimate 120 extreme is not placed properly, even though my temps are fine. I want to know what the inside temps are so I can gauge the difference between case temp, outside temp and core temps.

I am thinking my idle should be closer to my outside ambient temp.

Example of my problem. ambient outside temp in my room, 25-26c. Idle tat is about 40. Load gets upto high 40's never more than 50c using dual prime95.

With out OC, but same voltage, my idle tat is 38-39c and load is never higher than 44c

set up is

e6300 at 431 x7 voltage is 1.20 (yes under volted)
GA-965p ds3
Ultra 120 extreme with a 120 scythe flex
Big *** case with 2 120's as out fans (back and blow hole)
and 1 120mm intake front bottom and a 80mm on side

I think Thermaltake makes somethign you can stick in one of the CD-ROM drive bays. It has a digital temp readout and comes with a few different probes you can place in different parts of your case.

I think your temps are just fine and low enough, my Athlon XP 3000+ runs 48c idle and 52c on load an the ambient is ~26c.