Soon the way you use your mouse could help prove who you are.
How you use a mouse is very personal
Scientists have found a way for people to sign their name online using a mouse instead of a pen.
The security system uses smart software trained to recognise the way that someone uses a mouse to write out their name or another identifying symbol.
The system could be used to verify that people using a website are who they claim to be or provide another level of checking when people use credit cards online.
Created by computer scientist Dr Peter McOwan at Queen Mary, University of London, the software system uses a neural network to pick out the unique features of the way that someone uses a mouse.
"It's about using the mouse as a kind of surrogate pen," said Dr McOwan.
"You could sign your name of another reproducible figure that you can use in place of your signature," he said.
The neural network inside the software needs about 20 examples of the way that someone signs their name with a mouse to learn its important characteristics, said Dr McOwan.
How someone uses a mouse is as distinctive as the way they use a pen, said Dr McOwan.
"It's an extra biometric layer on top of traditional passwords," he said.
"It's another way of indicating that you as an individual are sitting there on the end of the line."
Dr McOwan said the system is easy to install on machines as it needs only software to operate. It can keep an eye on the way that someone uses a mouse and refine information about distinctive mouse movements over time.
The security system works with both optical and mechanical mice.
Early trials of the system on students in the computer science department at Queen Mary showed that it was 99% accurate in spotting who was using a mouse to sign.
You can hear more about using your mouse for your signature on the BBC World Service programme Go Digital.