Sys/x
From Wiki
< Sys
Sub-area Sys/x is reserved for ad-hoc, unregulated extensions on the server side. It has no other content aside from this page. It serves mainly for unregulated namespacing, and all it offers in this regard is a guarantee of no name collision with other sub-areas.
Alternatively, you may wish to use a name beginning with a lowercase letter. These cannot collide with top-level names in the wiki because the first letter of a page request is always mapped to uppercase.
Nobody actually uses this sub-area, yet.
