"Greeking" the text of a web page lets you focus on the layout and check that the visual structure gives users the right kind of clues. In the past greeking a page has not been all that easy, but now all you have to do is type the URL below and print off the results. (Note that at the moment, pages linked to are not greeked.)
If you find you are getting strange results (remember that the unintelligable text is deliberate!) make sure that the URL you enter is correct and is not being redirected. Also, because greekthis.com is pretending to be an extremely stupid browser, some sites produce a simplified layout to accomodate it.
(For anyone interested in more background to this approach, Jakob Nielsen reported on a study by Tom Tullis in this Alertbox article.)
Other Usability and User-Centred Design Resources from Syntagm: