The absolute oldest cel in my gallery (that I 
can remember..hehe) is the one pictured below.

If I can remember way way way back, this was the 
second Ryoko cel I ever purchased.  The first 
one was resold a long time ago because it just 
wasn't "up to par" with the rest of my 
collection at the time.  Animechaos wasn't even 
around back then.  =P

Lots of people guessed "OVA1", "First1", or any 
other series with a number "1" in the file 
name.  Good strategy, but a year or so back I 
rescanned all my cels and didn't keep them in 
any specific order.

Anyway, to the person who won, look for a little 
something extra in your next order.  :)