In my endless effort to combat spam, I've implemented the Hiveware Enkoder from Dan Benjamin. The Enkoder completely removes my e-mail address from the site, at least as far as e-mail-harvesting robots are concerned. Dan writes:
Instead of merely breaking up and printing out a standard mailto: tag, The Enkoder generates a unique and random key and ties that to an encrypted array containing your address for even better protection.
I have been doing a kind of half-assed version of this for a while by using "justin at justinblanton dot com" on the contact page, but that method obviously disables the ability to simply click on the address. With the Enkoder, I can retain the "firstname.lastname@example.org" phrase and the link.
On a related note, if you plan on implementing this yourself and decide to use the Enkoder Form, it won't produce the correct output in the latest Opera release (v7.1; perhaps earlier versions as well). You'll need to view the source of the webpage and copy the code from there. The author has been notified of this slight quirk.