Originally Posted by MERTON
what would really be nice is aero water bottles.
that way you don't have to worry about the wind resistance they cause but you can still scratch your back.
There have been a few different kinds of aero water bottles made. They can be found on ebay once in a while. The old Campy ones are nice looking, however...
Wind tunnel testing has shown that, if you have a bike with round frame tubes, having two round bottles in cages on the frame is more aero than not having them.