Hanged vs. hung came up today on ADS-L, so I quoted from MWDEU‘s nice entry on the subject, with this admirable (and somewhat testy) conclusion:
The distinction between hanged and hung is not an especially useful one (although a few commentators claim otherwise). It is, however, a simple one and certainly easy to remember. Therein lies its popularity. If you make a point of observing the distinction in your writing, you will not thereby become a better writer, but you will spare yourself the annoyance of being corrected for having done something that is not wrong.
That is, the annoyance of being incorrected, a k a miscorrrected.