slightly off-topic - for those of you who are not aware how gravatar works, it takes an unsalted md5sum of your e-mail address and uses that to request the really well done cute gravatars from gravatar.com.
Gravatar is owned by automattic.
So once automattic has your e-mail address, all they have to do is take the md5sum and they can track every single website you visit that makes a gravatar from your e-mail address and build a profile of you.
It is a really slick sneaky way for them to harvest data about you without it looking like tracking software.