Yeah, that works. It's unclear what the original poster wanted to do for multiple lines. I assumed that the counts should be cleared. In which case you'd do something like this:

$ perl -pe '%counts=();s|(/\w+)|$1 . ++$counts{$1}|ge' logfile>counted
+logfile
[download]

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<http://www.dave.org.uk>

"The first rule of Perl club is you do not talk about Perl club."
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