This is my very first instructable so tell me what you think. I looked on here for computer mod stuff and only a few things turned up,(making a window, etching on your window) so I decided to give all of you computer modders the full version of "modifying your computer".
Materials you will need:
1)plexiglass
2)small 1/2 to 3/4 inch screws
3)drill with bits
4)a way to cut your case material (in my case a dremel cut right through the metal)
5)hand screw driver
6)masking tape
7)File
8) 1/4 inch tubing
8)anything you think would look cool on your computer (I used some neon orange wire sleeve, blue cold cathode light, light up ATA cable, and SATA led cable)
There is so many computer mod sites I used http://www.xpcgear.com/casemodding.html

Step 1: The Window

The first and most basic computer mod is to add a window. So lets get going.

The first thing you will want to do is decide if you want to have just a hole, a hole with tubing around the edges, or a hole with tubing and plexi-glass (a true window).

Take off your door panel and look at your computer for any parts that will prevent your door from fully closeing. In my case it happened to be a support beam for my power supply and the lip at the rear of my case. These parts caused my first attempt to fail. So measure and measure again.

Add 1 1/2 inch of clearence to your measurements to allow for the extra plexi-glass. Then mark your window on your case useing some masking tape and start cutting.

Step 2: The Window Cont....

Now start filing the rought edges and round the corners, for those of you that totaly ignored that step you can get some 1/4 inch tubeing and run a slit the legnth of one side of the tube. Run the tube around your window. If you feel safe that nothing will get into your computer (pets, little brother, liquids of any kind) then you can leave it open otherwise continue on.

Take your plexi-glass and cut it to fit you window with about 1 1/2 inches extra on each side. carfuly drill a hole in your door that is slightly bigger than your screw, now center you plexi-glass over you window, you should be able to see the hole in the door that you just drilled. Carfuly (don't push to hard on the plexi-glass) drill a hole that lines up with the hole in the door (make sure the hole is smaller than your screw). repeat this untill your plexi-glass is secure. TA-DA you have a window.

If my directions were a little unclear you can check these two sites, I found they helped my a lot https://www.instructables.com/id/E0TPGA73GTEP287FTT/
http://www.amd.com/us-en/Processors/ComputingSolutions/0,,30_288_13265_13295%5E13330,00.html

Step 3: Adding Wire Sleeves

This is pretty easy but you pretty much buy them (http://www.xpcgear.com/casemodding.html) and plug them in but heres what I found that really helped.

I first unpluged everything from the mother board except the CPU fan (that is assuming you can put everything back together). I only had 4 feet so I was limited to my choice of cables, I picked my 4 pin connector, LED/speaker wires, and another unknown cable (I just know where its goes not what it does). Anyway you just slide one end of the sleeve over your cable untill you have reached the desired legnth (mine was as far as it could go) then cut the sleeve off at the end of your cable. Add cable ties to prevent the sleeve from fraying and you're done, pretty simple.

Step 4: Adding SATA and ATA Cables

This is a little bit harder but still pretty easy.

To add a SATA cable you should unplug your hard drive and remove it from your case then plug one end of you SATA cable into the motherboard, find a nice hiding sport for the little box and stick it down useing the tape they provide. Plug the box into a 4 pin power thing and re-attach your hard drive.

Its the same concept with ATA cables (CD-rom cables) just instead of the hard drive being removed the CD-rom is removed.

Step 5: Cold Cathode Lights!!!!

This is pretty much the same as the previous step but oh well ill do it anyway.

First I recommend the small 4 inch lights because they go almost anywhere in you case, if you get 4 inch ones I recommend getting two (that means two packages of two lights).

Get out the switch (that should fit in a PCI slot) and screw that down. Then connect the switch to the box, Then hide the box and tape it down using the tape they provide (but it has to be close to where your lights will be placed). Mount the lights using the tape/velcro that they provide and plug them into the box. Now connect the switch to the 4 pin power connector and you're done.