I'm bored with the desktop images and screensavers on my iMac, Dave. I work for NASA and would like to have a random set of space and science images used instead, and am fine if it's the same photo library for both the desktop and screen saver. How do I set that up without buying a screensaver library?

I saw your earlier article about how to set up your Mac so that it requires a password when waking up from sleep or from the screen saver (see password required to wake Mac from sleep). Nice. Now, how can I do that with my Microsoft Windows Vista PC laptop?

My kids are driving me a bit crazy: they keep opening up my MacBook Pro and messing around with it, even when I tell them not to. Since I can't hover over it like an eagle, I need a software solution: how do I require a password to be typed in - to password protect the computer - on either wake from sleep or going from a screen saver to the regular desktop on Mac OS X Snow Leopard?

How can I change the picture on the background of my Mac? I know it's probably easy, but I have no clue.