How vulnerable is a 'Limited" account on XP?

I've been wondering: are there exploits/vulnerabilities that can burrow into a system through a limited account on XP? I've tried playing around a little bit [but I'm really not very much of an XP-hacker] and it sure seems hard to get a toehold on the system from my limited account. With the entire system drive essentially read-only, and with its not being able to mess with ADMIN or SYSTEM processes, I wonder just how vulnerable XP is... [for example, I"ve been tempted (but too chicken) to try intentionally infecting myself with one or another of the email-borne viruses just to see how far they could penetrate into my system].

  /Bernie\

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Bernie Cosell                     Fantasy Farm Fibers
mailto:bernie@fantasyfarm.com     Pearisburg, VA

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