this has been done before, so instead of showing you a regular expression i'll show you this:

use File::Basename;
my ($name,$path,$suffix) = fileparse($path, qr/\..*/);
[download]

this is easier and more portable than a regex.
(update: ok, the suffixlist in fileparse indeed is a regex, but no need to care about slashes or other delimiters in the path)