Thanks!  I've built a few thousand computers in my day so they are well put together. 

Once I sell the 6990's I will probably sell the rest locally.  The cases pictured have been um..."violated" would be a good term, for a ducted cooling solution so I plan on buying some generic desktop cases and slapping in the DVD drives that came free with the rack cases (thanks newegg!).  I figure they will make a nice little gaming rig with a 6970 and a 1050 PS.

As far as hosting at a friends house, there's always the question of the ~$3/day they use in power.  I'd rather sell them to someone who wants to mine on their own than get involved in a profit-sharing arrangement that may only end in bad feelings and broken friendships.  That and the current heat wave is making me think maybe what I really need is a nice car with AC.