... My 2¢

As you know I am also a currency collector (ISBN). There are a great number of websites that display collections but they each vary in focus. Ron Wise, also a ISBN collector began assembling a 'grand' collection of notes he owned, notes donated, and scans donated, totaling some 20,000 scans! Other collectors often use the site for reference since it is so complete- the site draws a crowd both collectors and non-collectors & contributes to new membership as well. Other collectors seeing 'holes' often scan a note and submit it, many notes are beyond the reach (cost and rarity) of many collectors. The site is probably one of the best there is, and the ISBN adopted it as it's "Official Gallery". Plus it is free to use provided:

The images will be used for your own viewing pleasure. Or, You will use the images to promote World Paper Money collecting. Or, You will use the images in some form of educational capacity. Or, You will use the images in your personal homepage.

I have always wondered why the Chip collectors do not have a central site for virtual image collections. That would be a GREAT start. IMO

If you would like to look at their site for ideas: http://aes.iupui.edu/rwise/

(OK I will sit down and shut-up now )