Called my cell phone, left no message. Called back using *67, got fast busy initially. Called again and got same message as shark12. Listened for 5 or 6 repeats of their "Lisa" message then just set the phone aside to let it repeat itself to tie up their lines, if even a small fraction of a percent. Not sure how long it went on.
There are limited-function cell phones available. No internet, no aps, just calls. Some providers even offer phone tracking so you can find the location of the phone, and thus the owner, by internet anytime you want. That sort of phone would be perfect for a 10-year old who gets home from school while her parents are still at work.