http://www.sitepoint.com/blog-post-view.php?id=256428

The link back to the blog on the breadcrumbs links to http://www.sitepoint.com/blog-view.php?blogid=256428 (same id, but to blog-view.php), which obviously gives an error.

You also have a link to the UA and XML blogs that go to dead pages (along the bottom left).