This should be filed under "What the fuck is wrong with people".
Here's the user agent with a hyperlinked smiley face to some bullshit website in The Netherlands:
18.104.22.168 - "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; <A HREF=http://jult.net>;-)</A>; .NET CLR 1.1.4322; InfoPath.1)"Looks like some asshole might've done this to his browser as the request did have a Google referrer so it's probably a real human that landed on my site.
Well pal, you got an error message when you hit my site didn't you?
Bet you're not so fucking smiley faced now.