Youtube 500 Server Error

So, for all of half an hour between 22:00-23:00 GMT YouTube had a lovely 500 Server Error, with a 4150(ish) character hash on every page refresh. Streaming servers still worked, so all of those watching longer videos may not have noticed anything.

Everyone else saw this:
youtube 500 server error
The text reads:

Sorry, something went wrong.

A team of highly trained monkeys has been dispatched to deal with this situation.

If you see them, show them this information:
...some long hash

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