Nowadays many laptops are implementing this technology, the best example- Lenovo. So what does a Face Recognition technology do? It ensures computer access to authorized users only. Any other person trying to log into your pc won’t be able to do unless he’s authorized or he got your face peeled off, and you don’t want that. These are computer applications for automatically identifying or verifying a person from a digital image or a video frame from a video source. One of the ways to do this is by comparing selected facial features from the image and a facial database.
By contrast, face-based biometric identification allows you to enjoy face recognition login without having to spend too much money. All you have to do is look at a web cam for a second and the software will instantly identify the user. This effectively allows users to log into their computer just by sitting in front of it and looking at the camera. Here’s a list of good Computer Recognition softwares for Windows available free or you just have to buy it ;P
Banana Screen by Banana Security

Like the future? BananaScreen adds face recognition login to your webcam-enabled Windows computer. To use, just install BananaScreen and create a face model. Then set up BananaScreen to lock after a predefined amount of inactivity (or hit Alt-L to lock at any time). Once locked, BananaScreen will keep an eye on faces coming and going in front of the camera. When it matches yours, it immediately unlocks your computer. Cool, huh?
Lemon Screen by KeyLemon Inc

It automatically locks your computer when you move away and unlocks it back when you are again in front your PC. It is a simple fun and convenient application to lock and unlock your computer using your face. There’s an interesting feature known as- Hijackers tracking. Using this feature you can view pictures of the person who was in front of your computer before automatic lock and who typed a wrong password when computer was locked.
Luxand – Face Recognition: Login by Looking At Your PC

One solution which makes face recognition login possible is Luxand Blink! Pro, A program that negates the necessity for fingerprint scanners or the typing of lengthy passwords. What’s more, the software supports all webcam types and also accommodates for many different lighting conditions as well. To make it more versatile than ever, it also recognizes faces which have different makeup, fashion accessories or different haircuts. You certainly don’t have to worry about the software not being able to recognize your face just because you have a different hairstyle or different makeup on one day.
FaceAether by Brillertek Corporation

Brillertek’s unique patented cutting edge technology provides the best security to your computer. No longer are cards keys or tokens required for they are easily lost. Nor is there a need for PINS and passwords which are easily forgotten. Your face is what you are; your face becomes the key! With nothing but your face you can protect and guard your notebook or netbook and prevent third parties of unauthorized login.
Faceky by In-Sense Technology Pte Ltd

In-Sense Faceky is a facial recognition technology (RFT) software application that provides high speed recognition of facial images captured with a webcam, yet maintaining a low system requirement.