As more and more paper-based document workflow systems become digital, the main 'stumbling block' is how to digitally sign these documents. This video demonstrates how easily Digi-Seal™ Service [1], provides the ability to sign any PDF document, in any digital workflow system.
Links:
[1] https://www.digi-sign.com/digi-seal/service
[2] http://www.youtube.com/watch?v=bhUDdQrFhEM
[3] https://www.digi-sign.com/product/digi-seal/service