Back in January, I’ve
very thoroughly elaborated on the problems of Safari with some pages like
THIS and
THIS partly caused by the lack of any kind of character size increasing (and, with the Thinkpad thread, the lack of correctly reflowing / breaking long words / URL’s).
Thanks to apple.com forum user
‘ihadmeavision2’, I’ve found a
forum post that explains what needs to be done. It’s very simple: just put the following scriptlet in your Favorites list and whenever you’re on a Web page that uses unbearably small characters, just tap on it:
[i]javascript
:for(i=0;i<document.getElementsByTagN ame('*').length;i++)void(document.getElementsByTag Name('*' )
.style.fontSize='18pt');
Please consult
THIS for more info on how scriptlets can be added to Safari and all scriptlet-capable third-party iPhone Web browsers; most importantly, iCab Mobile.
Some before/after shots:

(from the original thread)
(the
Thinkpads.com thread. Note that the Safari engine has been fixed since January; now, “only” the message that has the long word / URL is rendered with a very small charset; all the others can be easily zoomed in with the usual double taps (old sceenshot
HERE). Also note that increasing the character size with the oversized URL didn’t result in being correctly reflown; now, you need to scroll to the right to read the message, just like in the case of simply zooming in)
(
Pocket PC Thoughts, Landscape mode; note that, in the meantime, the PPCT engine seems to have been made much more iPhone-friendly with far larger chars than before. See
THIS and
THIS for the older screenshots.)

(
Pocket PC Thoughts, Portrait mode)