in Under Hill (http://intimations.org/fanfic/supernatural/Under%20Hill.html) by Astolat, there is a passage were they shower together. (it's wincest)

That was awesome! Thanks for the rec!

You're welcome. It's one of my favorite fic ^^

A personal favorite of mine is insertcode11's This One Thing (http://insertcode11.livejournal.com/47739.html) awesome AWESOME fic

Oh! I remember this one! Thanks for reminding me about it!

I hope self pimp is ok.

I wrote a short fic a few years ago and for some reason it is still very popular on ff.net.

Baby It’s Cold Outside (http://jennybliss.livejournal.com/83019.html)

Pretty neat! Thanks for reccing!

The "Folsom Prison Blues" chapter of Fumbling in the Dark (http://archiveofourown.org/works/181789/chapters/268399)has a shower scene (like any good prison story). If the link doesn't go directly to the chapter, use the drop-down. It's chapter 41. (Although I recommend the whole series.)

I love leonidaslion! I think I might just have to read the whole thing...

Oh, you haven't read it? OMG, it's FANTASTIC. Go read now.

*goes to read*

Fill a space in which two bodies float (http://neros-violin.livejournal.com/9540.html) by neros_violin. The bath scene here is extremely sensual and extremely hot!
The Miners' Lamp (http://hansbekhart.livejournal.com/225708.html) by hansbekhart. The shower scene is in its sequel 'I see you better in the dark' and is equally sensual and hot!

Awesome fics! Thanks for reccing them!