I think my favorite meme was "blue OP plz nerf" whenever Bob mentioned he was using more crimson than blue, because blue was much stronger. I thought that was an interesting mix of gaming and art culture.
I also liked the "gg gb wp" at the end - the standard "good game" and "well played" that got changed to "well painted", combined with Ross's "god bless". "gg gb wp" made its way to some of the regular game chats by now.