Not sure if spaced repetition is the best resource we have. I haven't researched it, but the question I have is: how much of everyday's information is stored in the unconscious. Using hypnosis people can remember long forgotten things(assuming these are actual memories and not produced by imagination).

I have actively tried to use unconscious processes to remember some trivial stuff. Easiest way to experiment this is when you can't remember someone's name. You know the feeling when you almost got the name, but it still manages to escape your mind. What I have done is just say to myself: This name will pop into my mind once I stop trying to remember it. And more often than not, once I have concentrated on something else(it usually takes few minutes), this name will pop suddenly into my mind. Same technique can be used with lost keys etc.

I find it interesting that we can schedule some tasks in our minds. A la "Start searching my lost keys, please". And upon completion it will trigger a notification.