the open url shortener
Short url's generated by uglyc.at contain the target domain.
http://www.huxley.net/doors-of-perception/aldoushuxley-thedoorsofperception.pdf
becomes:
http://uglyc.at/huxley.net/4
This way your url's will always be trustworthy and transparent. Most of the time anyway :-)
Your short url's will become a bit longer but they are human readable. Happy shortening!