Writing Webcam offers view of living like a dog for the Chicago Tribune, Alex Goldfayn describes how a couple of installed a home webcam in order keep an eye on their pet dog while they're away from home.
If you've got a broadband Internet connection at home, and a pet that you'd like to keep an eye on (out of concern or curiosity) this really is a great solution. I've had a "ScooterCam" for a few years now, which allows my wife and I to check in on Scooter, our dog, and it is also greatly enjoyed by friends and family. Here's a photo that was captured by my friend Kathy one day when she peeked in our pup.
Like the folks in the article, I use a D-Link DCS-900W camera. It's wireless, so it's easy to position and connect to our home WiFi network, plus its built-in web server means that I don't have to a computer turned on in order to access the image. I've also had good success with this camera's wired hard-to-find sibling, the DCS-1000, which is a fine choice if you happen to have a network connection near where you plan to use it.
Details about my setup are in Smart Home Hacks (see Hack #82 - Monitor Your Home with a Network Camera on page 295). There you'll find that in addition to connecting to the camera for a live picture, you can use a computer to automatically grab an image from the camera and upload it to another location, or send it to your cell phone, at either regular intervals or on-demand. But that's a more advanced setup, for the basic camera setup, it's quite simple, and quite rewarding.