Probably my best "pure" Poser picture is Dragon Worshipper. Believe it or not the clouds are not a background picture, but were created with Poser 5's Material room. (The moon, however, was a photo placed on a square primitive.)

I think my best picture that uses Poser figures was The Servant Girl's Friends, mainly because I love how the lighting turned out. Just about everything in the picture is from Poser, but it was rendered in Vue d'Esprit.