Some of the coolest apps in Apple's (AAPL) iPhone App Store are widgets that let you use your iPhone or iPod touch as a remote control.

You can control dozens of gadgets, ranging from your DVR to your computer or high-end digital camera. The best news: Many remote control apps are free, and most are a few bucks or less.

Click here to see 15 things you can remote control with your iPhone →

Perhaps the most practical is the free Remote app that Apple launched along with the iPhone App Store in July, 2007. It lets you control your computer's iTunes app from anywhere within wi-fi range. That means you can change songs or volume levels from bed, across the house, or even outside.

It also allows you to control your Apple TV set-top box -- if you have one -- and use the iPhone's multi-touch screen as a gesture pad. It's much better than the small, plastic remote that comes free with the Apple TV. (Other media center apps have similar remote controls for the iPhone, such as Boxee and VLC, a video player.)

Soon, you'll be able to control some Blu-ray discs with your iPhone, we learned this week. A new Fast & Furious Blu-ray disc, to be released on July 28, includes a "virtual car garage," which lets iPhone and iPod touch users see different views of the movie's racers and cars by using their touch screens.

But it's not just entertainment: There's also business cases, such as using your iPhone as a remote for PowerPoint or Apple's Keynote software, or to monitor video from security video cameras.

Click here to see 15 things you can remote control with your iPhone →