For those of you that are about to "discover" trailer towing,
congratulations, check out the motorcycle trailer towing forum.
I've been doing it for a few years and it has really added to the pleasure of long distance traveling for us.
I was a little resistant at first but my wife shamed me into it when she "insisted" that I bring along her favorite pillow,
the embarrassment of having a pillow strapped to my top box "convinced" me.
Like Joe said "the cooler" is one of the most welcome and important accessories,
not only can it save you money by keeping you out of restaurants,
but it adds so mush to the trip.
I can remember (with fondness) each and every one of the "side of the road" picnics,
we've been on, can't say that about restaurants.
Oh yeah, I've always carried a spare set of wheel bearings!