Is it possible to program an OS X screen lock? I want the ability to lock my Macbook at my command. I don't want a screensaver or sleep lock. Don't you get tired of repeatedly typing in your password in all day? I don't want to wait for my computer to lock itself in 10 minutes or 1 minute when the screensaver or sleep begins. I don't want to save and close all my apps and documents and logout.

So just let me lock my computer, simple request. Hit a hotkey? Close the lid?  

I walk out my door, I lock my door. I get out of my car, I lock my car. Why can't I just lock my computer?  

I've been told you can't reconfigure this type of setting in OS X, is this true?
On a Macbook, pressing ctrl+shift+Eject will lock the screen instantly.  These keyboard shortcuts are configurable from System Preferences.