^^^ If you hit "STOP" twice when the "Set Clock" screen comes up, you will go straight to record mode (the first press kills the set clock message and brings up the screen where you can set the time; the second kills that screen and takes you to the one you'd normally see after start-up). The files will be numbered Z0000001.wav, Z0000002.wav, etc. When you turn the recorder off, and then back on, the next file will be Z0000003.wav (in other words, it will not over-write existing files).
This comes in handy if you don't have time to set the clock, or don't feel like it, and takes almost no time...