Inreasing font size with javascript

Hi,

I would like to hear some opinions about increasing the font size using a jvascript/css solution VS using the browser(other than saying user are stupid which I don’t buy )

Here’s what I am talking about
http://labnol.blogspot.com/2006/12/allow-site-visitors-to-change-font.html

Thanks

found this to be the best js font-resize script: http://www.frontendplace.nl/bb/?p=399