I know this is immensely geeky and of no use to the average Facebook user, but my Facebook profile "about information" is PGP signed so people (who know how) can verify that it belongs to me:
FireGPG users can auto detect the signed text in the page and have it verify inline in the page.
Just paste the signed text into "cat|gpg --verify" and done.
I mention my profile ID and username inside the signed text to prevent replay attacks where someone simply copies my signed text and adds it to their own profile.
https://www.facebook.com/imike3 (You can only see this URL when logged in)
FireGPG users can auto detect the signed text in the page and have it verify inline in the page.
Just paste the signed text into "cat|gpg --verify" and done.
I mention my profile ID and username inside the signed text to prevent replay attacks where someone simply copies my signed text and adds it to their own profile.