A few nights ago, I was davening Ma'ariv in my local shul. Most of the shul is of the black hat/jacket type. I am one of the few who don't fit that mold - but that's all right. No one at the shul has ever harrassed me or even looked askance at my lack of jacket and/or hat.
That being said, on this particular night, I was dressed in a button-down work shirt (blue, dress-casual), no hat or jacket. A friend of mine was dressed in a button-down white shirt, tie, jacket... and a baseball cap.
The get-up led me to thinking... was wearing the baseball cap the right thing to do? If one applies the concept that one should daven as he would appear before a king, then I would think that the person should lose the cap. No one would go before a king with a jacket, tie and baseball cap*. Most people, I would think, would sooner go without the cap in just a jacket & tie. And even if you're going to argue that that's just a reflection of non-Jewish culture (which regards the removing of the hat as a sign of respect), you probably wouldn't go to the Gadol HaDor like that either. If you had to go and had no formal hat and the only choices were yarmulke only or yarmulke plus baseball cap, my guess would be that most would go without the baseball cap.
There is also the custom of having a double-head covering when davening. However, I wonder if this should be observed at the expense of making one look silly. What if the only "second cover" you could find was a jester cap (assuming, of course, it's not Purim), would you wear it for davening? Does the custom to have a second head covering really overrule common sense with regard to how one looks when davening in front of God?
What are your thoughts?
* Possible exception: if you were meeting the king at the ballpark and your cap was that of his favorite team.