I'm referring to the following post in meta.Math.SE where ALL of the answers are community wiki's which are used by people working on (long) questions or answers that are "in the works", need further research and editing prior to posting on the main site. The rules over there on Math are pretty straightforward, pick a "free for anyone to use" answer, use it, and release it back to the free pool by "clearing it" after you are done. The only drawback is, it will constantly show up on the front page due to numerous edits, but over time, people will get used to it and ignore it.
So, how about a Sandbox for Hinduism.SE on meta?
I can certainly see myself using it if it's there.
Of all users, I predict this user will benefit most from this, also we all get a sneak peek of what's in the works from him ;-)