Why not let land owners control an "Auto Return" for all objects Rez'd on their land, so that the current "Return" feature acts selectively by saving authorized objects and returning unauthorized objects. Authorized objects could be set through avatar names (note to self: remember to bump Nexus Nashes land objects post back up too, becuase those features would rock!).
I can think of multiple uses for such a feature that extend far past my own wishes.
1. Timed games where weapons/objects delete after a set period of time
2. Built in cleanup of time sensitive inventory objects, notes, textures, etc.
3. Easy automatic cleanup of unwanted prims on object Rez enabled land
4. Easy automatic cleanup of temporary builds
5. Dynamic 3D countdown timers
6. Timed auctions
7. Teaching tools
I imagine this feature would be an improved, combined, and refined version of what currently exists for land owners on their land objects tab and the "Temp on Rez" option for objects. Make a copy of the texture/object/script and set the "Auto-Delete" under "Properties" to produce a demo version. Anything embedded in an object contents would carry the "Auto Delete" setting for that object. "Auto-Delete" could be set for any amount of time between 1 minute and up. Zero would be the default disabled setting. Link this to avatar names under the objects option on land to clean up your land in a similar way.
Of couse, such a wide sweeping feature would have to be carefully thought through, which is why I'm interested in feedback. I'm not an expert in system/database architecture, so I'm just throwing it out for everyone to debate, chew on, shoot to hell, because that is how we innovate and improve SL
