Sure, laser pointers normally cost about a dollar, but how many of them connect to their own app? The Smart Dot, by Korean company Tangram, is a tiny brushed-metal accessory that fits into the headphone jack of a smartphone. Once connected, it can work as either a simple laser pointer or a mouse: an iOS app includes a trackpad and buttons for moving through presentations, and an Android app is apparently on the way. When the hardware is disconnected, it fits onto either a colorful rubber strap or a metal stylus that's also currently compatible with iOS.
There are already a number of apps that let smartphones control computers, but the Smart Dot is one of the first we've seen to offer general trackpad options. Tangram also seems determined to stuff as many functions as possible into its hardware without sacrificing good design. That said, the Smart Dot may not justify its price point. It's currently being sold in Korea for 49,800 won (about $45 US), and is supposed to see an international release later this month. The app and desktop software are free, but the setup is still pretty expensive for a presentation aid. If you're looking for a less extravagant way to control your computer, you might want to check out Gmote for Android.