Clever Princess was successfully taught how to use sign language, and was also nearly very successful staging her own escape attempt via a docked canoe.

BBC: Drifting down the Sekonyer

"Messages", an internet-based audio, text, and video conferencing application that is included with Macs, has high-quality video and frame rate capabilities and is ideal for people who use sign language to communicate.

BBC: Speeding up work for people with disabilities