What computers can't do
plus.maths.org
plus.maths.org
Cantors theory: http://my.opera.com/Vorlath/blog/2009/06/22/cantors-theorem and http://my.opera.com/Vorlath/blog/2009/07/05/cantors-theory-v...
The halting problem: http://my.opera.com/Vorlath/blog/2009/04/16/flaw-in-halting-... and http://my.opera.com/Vorlath/blog/2009/06/18/halting-problem-...
For a nice introduction to computability theory I suggest David Harel "Computers Ltd".
the way it should be!