There is this website, which shall remain nameless, but can be found at http://www.debeurs.nl, they used to have these forums for discussions about stocks and such. Recently they decided that it needed to be changed.
So, instead of designing a new site, testing it in a test environment and then rolling it out to production, they decided that was all just silly and there's no reason why you shouldn't replace a working site be one that is still in beta.
But the real killer is this:
If a discussion gets past a certain number of contributions, it is continued on the next page. And if you refresh that page, you are greated with the (browser) message that it contains POST data and do you really wish it to be reposted?
Their number one genius must have thought that it was smart to keep track of the page, by embedding an invisible form.