iCamSource is an app that allows you to stream the video of your webcam. It is the server-side app that powers the iCam iOS app. The iCamSource application is the server that allows you to share the video of your web camera. It supports up to four cameras, and you can see many on your iPhone. Once you have both apps installed, you can connect to your Mac or Windows PC from your home network or the Internet and see what is going on at home.
iCamSource supports a wide variety of web cameras. I tested it with my iSight and a monitor web cam and they both worked great. Setting them up was very easy too, and that should be the case even for novice users. While running, the app will display an icon on your menu bar. If you open the preferences window, you will be able to manage your cameras and play with the settings. There is support for motion detection and push notifications. This means that iCamSource can detect when something is moving on the screen and send you a message on your iPhone to tell you about it. You can dial the sensitivity up or down to your taste and disable push notifications if you want to.
iCamSource has worked very well for me in the past, and I see that it is still doing it well nowadays. The iPhone app isn't very expensive and it works very well, too.