mis jaksin said:it's the repti-fogger. i was a little leery about getting it because i've heard mixed reviews (have to be sure to use distilled water), but so far it's worked great to bring the humidity up in the air. after brutus basks for a while, he sometimes lays on the substrate under where the fog comes out... it's pretty cute, i'll crank the fog up and he'll raise his head up into the fog... he seems to like it.
it's still necessary to spray the substrate down a few times a week though. i use eco-earth substrate, which i prefer over cypress mulch, but it probably tends to dry out on the surface more.