The clip is taken from the movie Downfall - a serious movie on a very serious topic. As the original post says, though, "Just remember, it's not about Hitler. It's about Twitter." Still, turn your speakers off if there are any German-speakers in your office.
As Mathew Ingram noted, Hitler sure made some funny videos. Hilarious.
On a related note, it looks like Twitter may finally be getting over the issues that resulted in videos like this. At time of publishing, the site has enjoyed 99.95% uptime so far in August.
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