Don't have a webcam? why not just use ur phone!!

well well well. webcam using a phone... want to try it? download it from here http://www.ziddu.com/download/3611380/8_200807051709_mobiola_webcam3_3015_m2d_s60.zip.html

install it, then connect your phone using bluetooth or USB cable. then you can see a new video capture device under your Windows based machine. quite cool if you don't want to invest in a webcam.