None of the proposed regex solutions properly handle:

<img alt=">click here<" src="/images/button.gif" NAME=">click<">
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Yet Another Reason to use an HTML parser.

Updated:
None of the proposed purely regex solutions ... happy now? ;-)

Yes, the given regexes can all be modified to work with this (psychotic) example. The point is that parsing HTML is difficult, and that this wheel has already been invented a few times.