I was recently sent a few URLs by someone (Chuck Fresno - thanks Chuck - I don't know if you are on this list, or just stumbled across my web pages).
One of them contains some interesting 18-hint patterns, but it is in Japanese and has some annotations that I don't understand (babelfish autotranslation is not TOO much help).
Maybe some of the Sudoku experts on this forum can help to interpret the 3 numbers on the top-left of each puzzle...
http://www.geocities.jp/takinogawa001/h18/HINT18.htm
I like the pattern... Angus might enjoy it as well...
Cheers
Gordon