Fun idea, but what are the potential use cases? The results seem quite random, even the same image drawn slightly differently returns wildly different results.
I seem to recall Nat Friedman was working on this sort of "image search by drawing" stuff in a popular Linux photo app in the mid 00s but I'm still looking for the citation.
Does Google Search By Image not work in Opera or something?
The whole drawing part seems to work just fine, it then redirects me to Google where it's supposed to do Search By Image but I just get the Google Front page?
Tried finding logos with it (http://bit.ly/mOHZjx, http://bit.ly/rpHUOC), smiley face (http://bit.ly/p9EqV6), Piet Mondrian (http://bit.ly/pSxzap) and schoolboy's favorites (http://bit.ly/pYMeV6 http://bit.ly/nr7wxf) with no joy.
Anyone got it to find anything they specifically asked for?
Edit: Last two NSFW if you work in a preschool or something.