Auto Thread locking/removal

Well I had arisen a thread without thinking how old it was and an idea came from it...

I think it would be nice if newly created threads would have a "count down" clock for when there's no activity for 10 days. Of course you guys (devs) can change the time to how ever long you want it to be...

I'm actually considering coding up something similar to the "saging" system seen on imageboards.

Where people will be able to post to threads without bumping them, it'd be enabled by default on threads where the last reply was x days ago.