Here's a 40 sec. teaser for the Prolouge DVD:
http://navi.zoome.jp/atv/navi_fp?ent=198&thm=11
EDIT: Now here's a longer promo which I believe was shown in Comiket:
http://www.youtube.com/watch?v=FUfy5ZVENYo
This might have the potential of kicking ass!