All the commercial airplanes have something called black box to record all the activity during a flight. In the event of a plane crash, the engineers can check this black box to see what really caused the plane to crash. Using a similar principle some developers have designed a software called Automatic Screenshotter that keeps taking the screenshots of your PC screen at regular intervals. Through these screenshots, you can find out what was happening in your PC at point of time in the past. Of course, you can also use this program for a myriad of other reasons, for example, to keep the screenshots of your screen at various stages of designing a 3D model in an application like Blender.
Automatic Screenshotter is available in the portable application format and when you launch it, it sticks an icon in the system tray of Windows desktop. It keeps running in the background and by default captures your screen every 5 minutes. You can right-click on the system tray icon and change the screen capture frequency from 5 seconds to 1 hour. You can also force-capture the screenshot at any moment and pause the capturing through this system tray right-click menu.
In the options for the Automatic Screenshotter, you can disable screen capture for the screensaver and full screen apps (like games), disable capture when screen is idle, when the new screenshot is not much different from the last one, when the screenshot turns out blank, etc. You can also specify a folder where the screenshots are saved in the PNG format, specify the maximum number of screenshots to be saved, choose what to capture (full-screen, active window, active monitor etc.), and define a custom time frequency for capturing the screenshots.
Conclusion: Automatic Screenshotter can come very handy when you want to keep capturing your PC screen repeatedly after a fixed time interval. It supports capture from multiple monitors and can auto-stop capturing when you are playing full-screen games.
You can download Automatic Screenshotter from http://www.donationcoder.com/Software/Mouser/AutomaticScreenshotter/.