There's various symbols etched on the wooden halls of houses as well.
I love chasing the wild butterflies and fireflies. Next thing you know you're next to a giant.
In case someone hasn't mentioned yet (I'm not gonna bother reading all six pages, sorry), those aren't an easter egg or anything. They're symbols used by the thieves guild for communication, kind of like tramp's signs. You can find a book that tells their meanings.