Rails has a few ways to obfuscate mailto links through the mail_to helper method. JS encoding, hex encoding, and just text obfuscation.

http://api.rubyonrails.org/classes/ActionView/Helpers/UrlHel...

Solves the problem of getting spammed by email scraping bots. I'm assuming you could write your own helpers pretty easily in other languages / frameworks if they don't already exist.