Smartphone Spy Lens
If you want to discreetly take a photo with your phone, the Smartphone Spy Lens ($20) will help boost your espionage-cred immediately. This somewhat-creepy, periscope-like device attaches to the camera on your smartphone thanks to an included magnetic ring. Internal mirrors let you snap shots at a 90-degree angle, so no-one around you will know what you're taking a picture of.