Today we are going to use some nice tools available in Illustrator that can be useful in several occasions. I’ll create a Folder but the important thing is the technique more than the final result. I say this because the use of different options of the same tool can bring different results. After you have learned the technique it’s all up to your creativity.Create a New Artboard A3 size and fill it with black.
Create a rectangle that takes all the artboard and fill it with blue.
Double click on the Rectangular grid tool. The option tool window opens and you can mange some options. 
Use the following parameters:
Create the grid holding and releasing the left mouse button.
Set up the color and thickness of the stroke. I chose a light blue as color and 8 as thickness.
This is what you get
Select the object than go to Object>Ungroup.
Every single line is now independent from the others.
Select again and go to Object>Transform>Transform each.
Check the Reset Box and the Preview box and play with the options till you reach a good-looking result. This are the setting that I've used and the result.
Than you can make some adjustment to suite your needs. For example I added some company information and selected the logo place. 
