This will get rid of pretty much all trailing comments, except those which contain quote characters. This strikes a balance with not trying to strip hash marks that are in quotes as data. 
while( <> ) {
    s/\s+#[^'"]+\z//;
}

[download]
So, if you can guarantee that no hash marks are data except in quotes and that there are no quotes in your comments, this should be a simple way to do it that makes reasonable accommodations for using the hash mark in data. If you have any other ways to wrap data in quote-like characters, just add them to the negated character class and keep them out of the comments.

Update: Fixed a typo. 2002/05/02

In reply to Re: Support for hash comments on a line by mr_mischief
in thread Support for hash comments on a line by c

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