A playground is a safe environment, often with a fence around it, perfect for letting AI agents play while you keep an eye on them.

Signal/TextSecure is Free Open Source Software. There is no company behind the development of the App. It is the Software with the best security model so far. The cryptography behind Telegram is not what you would expect of todays crypto standards. A lot of security researcher have commented on this already.

Sure there is a company (Whispersystems) doing most the work behind it. As they state: "dedicated development is supported by community donations and grants". This is good, it allows for very focused development.

Open WhisperSystems isn't a company. WhisperSystems was a company, it was acquired by Twitter which open sourced TextSecure. OWS, is just a name for the community effort around these tools: https://whispersystems.org/about/

Yes, what do you want to know? :)

Samba has a flexible process model so you can choose what you want: forking, preforking, threading (bad) or a single (for debuging) process model.

For 3. you should take a look at OpenChange. It implements Exchange using Samba 4.0 libraries.

Do you know of any success stories with OpenChange? Thanks for the info.