One reason for fetching page headers instead of using ping is if you can't run the script from a host in your DMZ, and your firewall blocks ICMP.   It also eliminates false negatives if the website you pick doesn't respond to ICMP.   Or you could use this goody to nail up a dial connection - some ISPs don't hold a line up for ICMP but will, of course, for HTTP.

BTW, I changed the open OUT,">>",$log lines like so: open (OUT, ">>$log") to get rid of this error:
Too many arguments for open at lines (open OUT) near "$log or"
Perl 5.00503 on Debian 2.2.
    cheers,
    Don
    striving for Perl Adept
    (it's pronounced "why-bick")