12:08 p.m. on September 1, 2011 (EDT)
Hilleberg has a new floorless shelter that has mesh and Kerlon sides that is intended to fit underneath their UL10. It seals right to the ground and permits the use of a groundsheet that can easily be replaceable. Fitting up to two people, it will weigh 14oz.
If you scroll down on this link, you will see a picture and some preliminary specs.
http://hilleberg.info/sites/default/files/usersmanuals/H12-NewsFlyer-Small-070611.pdf
Being the inquisitive person that I am, I contacted Hilleberg for more specific specifications and here we are:
-Height - 4 feet.
-Length - 9 feet.
-Width - 5 feet.
That is an enourmous amount of space for 14 oz; coupled with vertical ends, this would be a good option for the taller folk. Because the UL10 tarp is just over 11 feet long and 9 feet wide, and the Mesh Ridge has kerlon fabric from the bottom up the sides, coverage and ventilation should be excellent and a good option for less exposed areas below treeline.