This is the $15 Aurora Borealis heat changing coffee mug available from ThinkGeek. The Northern Lights appear when the mug is hot, and disappear when the mug is cold and you're out of coffee. To the break room! You know it's a shame that with climate change and all soon there won't be any more Northern Lights. Just kidding, that's not how they work. Or is it? I just read an article that says maybe they'll get even more intense. I don't know, I'm just a guy who fills boxes with words about his penis until it's time to go home. Is it time to go home yet? *gets whipped by a guy with a scimitar* Holy shit, I work in the mines below the Temple Of Doom. Short Round, call Indy!
Thanks to Bravo, who agrees the worst thing about heat changing mugs is they're not dishwasher and microwave safe until your roommate or significant other puts it in the dishwasher and it becomes a heat unchanging mug.