[masraum]

Just really don't have to worry about it much these days. Cell phones should all change automatically, because they get the time from the carrier. Computers should all change automatically, and then it's usually simple to realize and change the couple of devices that are left like a microwave or stove. I do have an alarm clock with red LEDs from the 80s that I still use (for time, the alarm stopped working years ago) that I have to change.