My sprint bolt restarted on its own and now is locked in a "thinking" mode that says Android is starting... optimizing storage.
I had previously tried the soft reset (hold down power and vol up) several times with no results. I just held down power and vol down until the menu buttons started blinking. It took about 4 seconds. That rebooted the phone. I tried that earlier and it didn't work, so I don't know why it worked now, but phone has rebooted and is working fine. Note: was stuck on that screen for about 3 hours.