I'm REALLY surprised nobody mention something WAY easier. Your website is hosted on an external host. Why not create a http://whatsmyip.com style page on your personal website? Or use http://whatsmyip.com (specifically www.whatismyip.com/automation/n09230945.asp which gives you just your IP!). Sure it reduces the amount of perl coding to almost zero, so it's not really fun, but no need to deal with logging into the Linksys and scraping the IP there and all that trouble.
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