Well, I've recently accquired a few of my 
wishlist cels (Washu eating a watermelon, Inaho 
as a child, Ken-ohki, etc...) there are still a 
few that stay constant:

Any cels of Team Rocket from Pocket Monsters, 
preferably of Kojiro. If you have Kojiro in drag 
or any from the episode 'Kojiro and Guardie' 
('Holy Matrimony' here in the states), I'd be 
especially interested.

I'm also always looking for the elusive ending 
credit cels from the Master of Mosquiton OVA... 
I know they must exist, even if I've never seen 
one. I'm also looking for a good flashback 
(black and white) cel of Mo-chan from the OVA. 
Otherwise I've more or less got everything I 
want from this show.

Any cels from Twin Signal, although preferably 
of Signal or Pulse.

Thanks for looking! :)