Let your Webcam be your eyes and ears while you're away from home or the office. A simple Webcam costs about $20, and a good surveillance-software package with motion and sound sensors, video recording, and remote viewing from any PC with an Internet connection can be purchased for less than $50. NovoSun's free SurveillizCam Lite provides basic video recording triggered by motion sensors, but for remote viewing and audio monitoring, you need a full-featured program such as DeskShare's $50 WebCam Monitor (free trial available here).
For more-sophisticated security, IP cameras can be placed anywhere inside or outside your home or office to transmit their images to your PC over an ethernet or Wi-Fi network. D-Link's $152 DCS-G900 wireless IP camera, for example, lets you view the video it captures in any standard browser (see Figure 4
An important consideration when you're shopping for an IP camera is how it will be powered. Cameras that connect to a Wi-Fi network avoid the hassle of running ethernet cables, but they aren't really wireless because they require that you run a power line to them. Devices that support the new Power over Ethernet standard--or IEEE 802.3--need an ethernet cable, but they draw power from the cable, which eliminates the need to use a separate power line.