Market size: Medium (< 10,000,000 people)
Investments required: Medium (< US$5,000,000)
Expert rating7.25
Public rating7.2
Voting is completed
Now, thank's to Steve Jobs, we have touchscreens. Yet, to sign a document received though e-mail we have to print it, sign, scan and send it back.
I believe a touchscreen can be easily upgraded to accomodate the signscreen function, so you can read the document and sign it without printing out. It's especially beneficial for travellers who often don't have a printer when they travel by car or by train.