I like the untucked button-down look, but often times the tail is too long and it doesn't look good. I found this company that makes button downs with short tails, specifically so they can be worn untucked. I ordered one as an experiment. I got it mailed, wore it today, and it looks really sharp. Good quality and looks good.
http://untuckit.com/collections/button-downs
http://untuckit.com/collections/button-downs
Take care of those titties for me.