Consider Adobe's Digital Pen and Ruler Your New Hand Weapon
If a normal pen is mightier than the sword, Adobe may have just reinvented gunpowder with Ink and Slide. An app-packed digital pen and ruler optimized for iOS7 use—think drafting studio—in tablet form, it enables Ink to function as sort of a handheld Photoshop with pressure-sensitivity opacity.
It includes some of Photoshop's more advanced features, like content-aware fill, while Slide helps you draw everything from straight lines (obviously) to curves and perfect circles. To prevent from accidentally drawing with your palm when you rest your hand, both Ink and Slide include "palm rejecting" software.
They're made out of aluminum, and Ink comes with a fully customizable LED light at the top so it can emit any color you choose. Also, it's all cloud-based, so when you're done sketching on your iPad, your work's already saved on your desktop.
Aaron Miller is the Rides editor for Supercompressor. He's often said in the past that he couldn't draw a straight line with a ruler. He's not sure if Ink and Slide could change that, but he's willing to give it a shot.