I started the following group to keep color large format images in one place for reference. It has now grown to a nice size and I hope you all enjoy going through it as much as I do:
Some notes: These are all sheet film, 4x5" or larger. No rollfilm backs, scanning backs or other digital backs, and not even instant film types unless the image area is at least 4x5". It's a closely moderated group.
The main page of the group is: http://www.flickr.com/groups/large_format_color