Originally Posted by naquaada

Heh, as I was in school we had a bunch of 286's with green-display monitors... If you'd have hang an X-ray film in that room you got a picture after a while

Somedays we had a teacher who had no idea about computers, but we could go in the computer room as there was spare time. Then someone programmed a little batch file which made some PC beeper noises and printed a message 'Error: Water in drive A: Please contact support'. The teacher flipped out because he had no idea what to do

As I got in school the first time the MS-DOS ASCII Escape sequences (Control sequences) I wrote a little batch that changed the DOS resolution to low-res, the color to blue/light blue and printed a new starting message: "**** COMMODORE 64 BASIC V2 ****" Adding to autoexec.bat and you have some fun...

Some years later I tested some other MS-DOS batch things, and you can do some really nasty things with it. For example, a recursive batch that creates an infinite directory tree. If you delete the MS-DOS command DELTREE.COM you had to go manually (1000x CD) to the absolutely last directory, and then delete it normally.

Another thing is a batch which uses the text output redirection to a file, like "type >outfile.txt readme.txt". If you use >>outfile.txt the output will be added to the end of that file. If you create an endless loop like "type >>giantfile.txt giantfile.txt" you will create a file which exponentially increases its size! On modern computers you can fill in seconds gigabytes of harddisk space with this - only with 4-line batch file!

The screen invertion thing I had somehere else: Actually In Germany Apple computers are available at 'Kaufhof' which is a normal department store chain (hope this was the correct word), they aren't a specialized computer store. There was an iMac with mouse and keyboard, and Tiger installed. I played a bit with it, them some guy came and asked 'May I can help you?'. After a little chat I noticed that he had no idea from Macs, and I showed him some things - Terminal, Speech recognition, Photo Booth and different other things. And the screen invertion thing. The guy was absolutely impressed of the capabilities of a Mac, perhaps no one told him that although he should sell these things. As I was going, I could see from the escalator that he was showing the invertion trick to a collegue...