Cosplay is of course one of the biggest feature in the 81st Comic Market/Comiket. Thousands of Japanese cosplayers will gather for photo-shooting sessions by professional and amateur photographers. And you can find many doujin circles selling their Cosplay movie/photo DVDs at their booths.
"Bon Voyage!" ONE PIECE Cosplay ROM PV by Y+T
"Oshiete!! Mahou no Lyric" (Hatsune Miku) by Seven Dolls
"Umineko no Naku Koro ni" Cosplay PV by Seven Dolls
(Mami Tomoe from Puella Magi Madoka Magica) by FAGOTT
"Lucky Dog 1" Cosplay ROM (BL game) by chan9