The grid was an experiment with PHP and text files. I wanted to see how powerful a databasing system I could develop using only well formated text files. As you can see, it went fairly well. The Grid has no practical purpose, other than the technical exercise in developing it.
It could have been developed much quicker and efficiently using a databasing system like MySQL, however the real joy was in seeing if it could be done without, which it could. I essentially developed my own databasing system, that could be referenced with PHP.
Link - Grid
Code Zip - Here