Spotted the following in my logs a couple of days ago:
64.62.136.201 - - [26/May/2005:13:05:36 -0500] "GET /robots.txt HTTP/1.0" 200 204 "-" "Twiceler www.cuill.com/robots.html"
Using that Hurricane Electric IP, it fetched robots.txt a few times since then. Their website is not reachable.