I don't have a dedicated BOB right now.  But for my car or my pack for long day hikes, I have an Army Gortex bivy sack with the two sleeping bags.  It was expensive, but on Ebay, about a third of what it could have been.  But that's for Wyoming, and I'll hump the extra weight so I don't wake up with frost bite(not that I would, I doubt I could fall asleep).  I also have a Drizabone riding coat I just got for an early Christmas present.  That's my EDC shelter, sure beats a trashbag.  I also have a couple blaze orange hunting vests.  Better then surveyor's tape as a signal, plus if its hunting season it might mean someone'll think twice before sending lead down range.  
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A gentleman should always be able to break his fast in the manner of a gentleman where so ever he may find himself.--Good Omens