The posters as seen in the "Fifth hour" Nicostream are being given away! All you got to do is enter your name and stuff. (You must live in Japan, also.) http://miku.sega.jp/f2/ps3/special_keyword_present.html
Gugh, if only I lived in Japan and had a place to put up posters. A thing signed by kz is a thing that I must one day own...