You might find this interesting: We made a javascript function that trims leading/trailing spaces from field values, but found it did not include the nonbreaking space character (nbsp;) when it appeared.
Before fixing it, our function looked like this:
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String.prototype.Trim = function() {

return this.replace(/(^\s*)|(\s*$)/g, "");

}
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After discovering that values that included nbsp; were not getting trimmed, I found the following to be true:

nbsp; = chr(160) = xA0

So have now modified the Trim function to read:

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String.prototype.Trim = function() {
return this.replace(/(^{\s\xA0#}*)|({\s\xA0#}*$)/g, "");
}
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(Please note that I used CURLY BRACKETS in the example above, but if you use this, use SQUARE BRACKETS -- they just wouldn't display on this page when I typed them in...)

And it works!! FYI, to clean field values, our javascript code calls it this way:
document.forms[0].myField.value.Trim();
Hope this helps someone,
Susan Henesy

Originally posted as a Categorized Answer.