Where does Dave Snider get his wallpapers?

Every time Dave showed off code on the site -- or any time he showed off his PC/Laptop in general -- he always had great wallpaper on his desktop. I searched around, but still couldn't find where he would've gotten them.

Does anyone know? Or has he never said?

Maybe try wallbase.cc/ ?

I can't remember but I think it may have even had a filter for anime/porny stuff which was handy.

@hayt: Thank you for this!