[Rajendra] tipped us off to this really slick hack he’s done to allow his multimeter to tell the ambient temperature. He’s basically measuring the output of an LM35 temp sensor that he has mounted in the case. The circuit is extremely simple and only requires the sensor, a couple resistors, and a switch so that you can return to normal function. When finished, you’ll have a multimeter that will display the ambient temperature when set to to the correct range (0-200 mV in his case). The switch is there so that you can return your multimeter to normal function afterwards.  While [Rajendra] chose to display ambient temperature, you could just as easily create an external probe for measuring other things.