Just tried it in Firefox and Chrome and there's no error. (Sometimes the browser you use can cause the error.)
BTW, although Tm Fisher (About.com) is pretty accurate in his description, he's wrong about one thing - the server does almost always know what the specific error is, but "Unexpected TIF on line 30" isn't going to be very useful to most people trying to use the page, and that's the kind of error message that's actually generated. 500 just means "email the webmaster and let him know that he has a typo on his page".
But don't worry about 500-series errors on web pages - they mean that there's something wrong on the site, and there's nothing you can do to fix it (except try a different browser). Give it a few minutes and if that doesn't clear things up, give it a few hours. You can also try
Down For Everyone Or Just Me -> Check if your website is down or up? to check the site.