You could use server-side scripting to accomplish this; however, this would require the page to reload itself after a font-change-click.
You can use multiple style sheets, but you would need a client-side way of switching the style sheets, which of course is JavaSript. Or create duplicate pages of content and when the user clicks a button or link, they are redirect to the bigger/smaller font sized page; however, that would double/triple/etc your work load due to the use of duplicating content.
Microsoft Certified Professional (MCP), future Microsoft Certified Database Administrator (MCDBA) - May 2007
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