Su Doku (Numbers Solitary) puzzle implemented in Ruby with ANSI/console UI, though a QT/GTK+ interface would have better; I have not learned QT/GTK+ as yet 
Yes! I did it in just 2 working days, exactly 11 hours of writing, testing and, or debugging.
Freeware, fully working code, though implementation of difficulty levels is pending, but you may please have a look at: http://rafb.net/paste/results/dAVYcw41.html
Your feedback to _BalwinderSinghDheeman/AT/yahoo.com_ and, or usenet newsgroups shall highly be appreciated 
Regards,
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Dr Balwinder Singh Dheeman Registered Linux User: #229709
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