See the code:
http://pastebin.ca/183613
the "finditer()" call don't seems to return.
Playing with the re can bypass the problem but it looks
like a bug.
(I'm really sorry if I did something wrong and didn't
notice)

note: I can reproduce it with python2.5

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Attaching the test script.  I've modified it to save a copy
of the HTML page's data so that running the example doesn't
require accessing a slow web site repeatedly.

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I haven't dug very far into the code, but suspect this isn't
a bug in the regex code.

The pattern uses lots of .*? subpatterns, and this often
means the pattern takes a long time to fail if it isn't
going to match.  The regex engine matches the <link> group,
and then there's a .*?, followed by <b>.  The engine looks
at every character and if it sees a <b>, tries another .*?.
 This is O(n**2) where n is the number of character in the
string being searched, and that string is 93,000 characters
long.  If you limit the string to 5K or so, the match fails
pretty quickly.

I strongly suggest working with the HTML.  You could run the
HTML through tidy to convert to XHTML and use ElementTree on
the resulting XML.

With python 2.6 the program can be interrupted with ctrl-c (see
http://bugs.python.org/issue846388). I think this one should be closed
as a duplicate of: http://bugs.python.org/issue1662581

Done.

This problem has been addressed in issue #2636.

Extra checks have been added to reduce the amount of backtracking.