We're cleaning house so actually there's a bunch 
of stuff up on ebay from our household right now 
(most not anime related I admit) but I put my cel 
of Mikael with wings up there with the reserve 
set at almost half what I paid for it.  Semi-cel 
related there are two very rare design books, one 
of the TV designs from Vampire Princess Miyu, and 
a book full of genga/ concept sketches from 
Tenshi ni Narumon.