Project Umbrella has been sitting on a goldmine for quite a while already (as stated on NeoGaf) in the form of some never before seen concept art from Resident Evil 0 and CODE: Veronica.
These images were sent to them directly by freelance concept artist Satoshi Nakai, who worked with Capcom back in 1997. Throughout the years, a small amount of his artwork has made it out to the public. But now we have a whole bunch of images from the aforementioned games and some of them are pretty damn horrifying. I wish some of these monsters actually made it into the game!
You can check out the source link below to be directed to the gallery with all of the images.
[Source]