Googlewhacks were popular a few years back. The next step: Googlewhacking the Google Image Search.
For example:
Busty Fish
Whacky Kitten
The game? Come up with a two word Google Image search that returns only one picture. Include that image on your webpage, renaming it with the two words you used to find it (both of which must be real words, as indicated by their link in Google to dictionary.reference.com). In all likelihood, Google will incorporate your copy of the image with the DB, thus bringing up two images when you do the search.
In this case, I’ve tried it with the images returned from searches for busty fish and whacky kitten.
This is probably really easy. That, or I found two in 30 seconds because I’m a Googlewhack Master.
Probably the former.