With the demise of Virtual caches and the increased usage of Nano caches, I would like to propose a new cache type.
A physical cache that contains a question applicable to the cache that must be emailed to the cache owner prior to logging a find.
Why? Paper in Nano caches is easily destroyed - particularly if it is desirable to record more than half a dozen initials / dates on it. The solution is to have a small piece of paper that is less likely to be destroyed, with just a pre-printed question on it. No requirement to sign / date it.
The cache owner could also then change the question regularly to ensure that the same wannabes who flit around the world in a few hours, logging virtuals, could not find out the question (from a 'real' cacher?).
There have been two nano-caches that I know of that have been archived recently as they contain a question like I propose. They were changed by the cache owner(s) from a 'traditional' cache due to the difficulty in maintaining the log. The 'question' works well and cachers who logged the find were receptive. The local reviewer thought differently - and of course their ruling is in line with the guidelines.
As this 'game' progresses, I feel that we should not remain 'traditional' but should allow some 'innovation'. After all, the types of containers are multiplying and I think the 'cache type' should evolve as well.