I wrote an article on dirty linking tricks and then I find I had an error in our updated robots.txt file. I updated the robots.txt file using one of our old ones that restricted a directory no longer used by the software. That directory is now used as our resources directory. Simply too many copies of old files for recordkeeping got in the way.
However, I did find the problem and fixed it as soon as I found it. I apologize to our great link partners and promise to never let that happen again.