Like this? http://www.fanfiction.net/s/5353360/1/Coming_To_Terms

How bout this one? http://www.fanfiction.net/s/4638266/1/Children_of_Man

Castiel loses his angel powers for a few days and has to deal while tagging along on a job with the boys.

Castiel's character was dead on and i loved the parts where he talks to a priest. It was all kinds of irony and just pure...awesome

http://trolllogicfics.livejournal.com/59658.html

Hope this is what you had in mind: The Consequences of Falling (http://pandarus.livejournal.com/248406.html) by pandarus . It's a "A story in fifteen parts, in which the angel Castiel finds himself put in an untenable position, and consequentially loses his grace. In which he goes on a roadtrip with a demon, discovers the delights of tequila and french fries and pie, plays a starring role in a virgin sacrifice, is deflowered by his favourite Winchester, and then gets some very unpleasant news indeed." (The summary does sound a little flippant, but those "unpleasant news"? *heaves sigh* My heart broke...) (Well, and there's sex.)
There is also a podfic version of this story (http://audiofic.jinjurly.com/consequences-of-falling), if you like podfics you should definitely check it out, beautifully read by the author.

Unfortunately I've already read that one, but you're right, it's fantastic. Thanks :)

I recommend The Serpent and the Staff by trinityofone located here:
http://trinityofone.livejournal.com/191861.html#cutid1

I was just thinking about this very fic but an hour ago. HOW DID YOU KNOW???