How can I benefit from the SE83 SAP Reuse Library?

I have just come across the SAP reuse library (transaction SE83), but have never used it before. In the current system there are only a few functions documented, some of which are actually flagged as obsolete by SAP.

Most of these functions/classes are also relatively well-known to anyone that has worked in SAP for any length of time, for example ALV Grids, confirmations prompts, conversion routines etc.

Does SAP release updates/libraries separately to the reuse library? Does anyone use it on a regular basis, either to find SAP released objects or to document their own internal functions?