Photographed by Geek Girl Diva, this Castiel was at this year's San Diego Comic-Con. Her impressive wings were attached to a pulley system so that she could retract them - it probably made getting through the crowds easier.
Cosplayed by The Naitsyrk, this is one of the few male Castiel costumes I've seen. He even went to the trouble of getting his hair cut to match the angel's, and he's wielding a wicked angel blade.
Cosplayed by MissArisugawa and photographed by KralikSetite, I like this casual version of Castiel's outfit. Castiel Lite, if you will. She's wearing a navy blue scarf instead of a tie and her tights feature angel wings.
Cosplayed by Becki, this version of Castiel in a mental patient's outfit is a callback to season seven. She did a great job with the makeup and beard stubble.
DeviantArt Shanea's daughter loves Castiel and dressed like him for Halloween last year. She looks scary, and reminds me that I don't see bloody and beat-up Castiels often. It's a good way to change up the costume.
Designer Casey/WanderingWindward was commissioned by a customer to build a "badass steampunk pirate version of Castiel." I'd say she pretty much nailed it, and I love this take on Cas' trench coat ensemble.