"The act of creating deliberately confusing jargon and user-interfaces which trick your users into sharing more info about themselves than they really want to. Usually associated with e-marketers and e-spammers." -Tom Jones
A Zuckerpunch is an "evil" interface is meant to trick users into doing things they don't want to. Greg Conti's examples include aggressive pop-up ads, malware that masquerades as anti-virus software, and pre-checked checkboxes for unwanted "special offers".
ref. Facebook's "Evil Interfaces." Tim Jones. April 29, 2010. Electronic Frontier Foundation - Deep Links (blog). Retrieved from: www.eff.org/deeplinks/2010/04/facebooks-evil-interfaces on May 1, 2010.