The deluge of smartphone cases out there means you can choose from nearly every color and style imaginable. But as far as we know, only one delivers Spock ears.
Etsy artisan Jeff Chris currently sells a $15 "Spock ear design" iPhone 4/4S case that features the familiar elven sideburns and pointed ear commonly seen on most Vulcan profiles. The silicone rubber case comes in either black or white, and should illicit gazes of wonder and curiosity as you mindlessly chatter away while walking in public. Just make sure to look both ways so you live long and prosper.
Surely, the wow factor of the Spock ear case diminishes greatly upon closer inspection, but one can at least confuse the heck out of people from afar for a short time. What other sci-fi ears would you like to see in an smartphone case?