Reusing Webcam and Monitor from old laptop
Ohh yes... I have been where you are :)



The one problem I ran into .. out of 5 broken laptops 1 uses USB interface :) the rest. well I searched and searched and searched.. most likely some propriety channels.

Looking at the number of wires does not neccesarily mean you can identify is it is USB or not. I have one with 8 wires and its USB, the others are for like switch, tilt, light sensor and most likely one for microphone i think.

The easiest way to identify if its usb is if you got the notebook running, looking in windows hardware management, and it will show under.. USB Video Device :)  Or a masked name by the "driver" but still under USB.

Usually if the vendor does not have a driver, it will be plug and play USB.



The most common notebooks that i have found that use USB are, Acer, Medion, many netBooks, some fujitsus. This is just a statistical number of my own research based on notebooks i had fixed.. 

Some webcams might just use +3volt, Video signal(usually yellow wire) and Microphone.
Some usb cameras have a seprate microphone line, others encapsulate via usb.

Now i have tens of cameras lying around.. and only 2 that work via USB... but I cannot justify running a PC on windows just to run a webcam :(

-EDIT

But soon you can just use the Raspberry the $35 to run as many cams as you want over internet on Linux/ possibly Windows 8 :)



Have fun!