Architectural Failures

I am holding a tutorial on Architectural Failures at SPA 2005 in the UK the week after next (see https://www.spaconference.org/content.html ) and am looking for any examples that I can use.

I have a couple where bad application distribution or poor availability design caused problems but was wondering if anyone had any experience of poorly architected systems that failed (not yours of course.. a friends!) that they could share with me.

Happy to chat on the phone for 10 mins to capture the essence if that is easier.

Thanks!!