The Sidearms Special manual "poster" isn't really a poster... I mean, it DOES fold out like a poster, but it's just got the manual on both sides. There isn't a picture. It's six CD covers large. Download is similar, except its fold-out manual is only four covers large, so it's even smaller.
Bulk Slash on the Saturn is similar; there's a cover glued to the inside of the case, and a removable six-CD-size fold-out "poster-style" manual is inside. But do these really count as posters when they're just manual information on both sides? It's not like those actual posters pictured in this thread from Fighting Street or Monster Lair, they're just fold-out, poster-style manuals.