My friend Alex posted a message on Facebook yesterday of his House Sigil. He's a Game of Thrones fan (though is miffed that the TV series is called by the name of the first book, not the overarching title) and had a lovely explanation of his choices.
I, on the other hand, have never seen an episode of the show and have no real interest in it despite the accolades that have been showered upon it. But I know a good artistic idea when I see one, so I burned a few hours (when I wasn't sick as a dog) creating a Sigil for my Saucerbottom alter ego. Of course, then he posted a link to HBO's Sigil meme generator. (Mine's better, even though they had a pretty cool squid on there.)
The motto is a Latin variation of war cry of House Saucerbottom: "Yes, have some!"