I think the best TV bloopers are on home shopping channels:

No matter how many times I watch this one it never gets old.  The guy at the end is the best:
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Next, we get to hear exactly how clear the sound is on this TV.  Anyone familiar with the movie should know what's coming up:
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Here's another classic.  The caller even tries to cover for it.  One of the hosts blames a "slippery floor" but the fact is that the guy is just a klutz.
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While we're on the subject of ladders.....
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Finally, my personal favorite.  This might be the only one that didn't completely kill sales of the product:
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