http://developer.yahoo.com/yui/theat...conf2009-state

It's quite interesting. I had never heard about the problem with IEEE-754 in ECMAScript/JavaScript that he talked about.

JavaScript Code:
  1. var x = 0.1;
  2. var y = 0.2;
  3. var z = x + y;
  4. alert ('0.1 + 0.2 = ' + z);
  5. if (z == 0.3) {
  6.     alert("0.1 + 0.2 == 0.3");
  7. } else {
  8.     alert("0.1 + 0.2 != 0.3");
  9. }