The Raspberry Pi allows you to connect a camera, either a dedicated one or a Webcam which can be connected via USB port. This post covers how to get an USB Webcam to work.
If your Raspberry Pi is connected to the outside world it is vulnerable. In one of previous post I have described how to make web server out of the Raspberry Pi. There you can find how to make it visible using DDNS.
There are few simple steps which you should follow to secure up your tiny server.
Time has come to experiment with Raspberry Pi which was getting a bit dusty.