may i take this occasion to strongly recommend (as a webdesigner) that you switch to Firefox ? IE (*especially* version 6) is a piece o' crap (full of security holes, webstandards out the window...), and no-one at ALL should use it.
also, using firefox you can resize easily the text on MobileRead (as JSWolf explained). i have tested just now and it works, i've never seen a site where it did *not* work unless the site used flash or images (not editable html text).
plus, it's free. http://www.mozilla.com
it's a much better browser overall.