What are good exercises for upper back which you can preform in the hotel room?
I only have my bodyweight and that's it. Also, I'm not very keen to test the strength of the various hotel's bars/rods by preforming pull-ups / chin-ups on them.
There's two products I would recommend (I hate to push a product, but these are relatively cheap and effective):
Specific for the back, I would agree with VPeric - using a towel on doorknobs, I would also recommend looking at Ross Enimait's homemade isometric tool/workout: http://rosstraining.com/blog/2009/02/23/homemade-isometric-tool/ Isometrics are VERY effective and with this device there's a wide range of back exercises (specific to your question) that you can do.