Some times, I find myself checking my e-mail, and wondering 'jesus, why do these people e-mail me! I wish there was a stupid filter'. I had another e-mail like that this morning, and did a search for 'stupid filter'. Lo and behold I got a hit.
Stupidfilter.org is an intelligent (as in supported-self-learning, although in this particular circumstance, that'd make a pretty good pun, too) bayesian filter which is designed to analyze text, and assign it with a 'stupidity' rating. The filter works in much the same way as, say, SpamAssassin does for spam, but instead of looking for V14gra, it looks for other patterns which might be consistent with stupidity.
The Stupid Filter will look for teen-speak (r u @ home, m8?), leet-speak (d00d! 1337!), lack of punctuation, too much punctuation (16 exclamation marks in a row, for example) lack of (and excessive) capitalization, excessive misspellings, etc.
By their own admission, the stupid filter is elitist as hell, but that, as they say 'is sort of the whole point'.
Myself, I can't wait until there's version of this that'll plug into my Google Mail account. I can just see the e-mail conversation now:
"Hi, sorry I didn't get back to you on the e-mail you sent to me 6 weeks ago, titled 'hi ur invitd 2 my partie'. Unfortunately, it was lodged in my stupid-people filter. Obviously, the party was about 3 weeks ago, but I don't think I would have liked it anyway, as I've developed a severe allergy against stupidity. Say hi to dad from me. -SharQ"
You can test it for yourself here - http://stupidfilter.org/demo.php .