Here's a quick guide to modding your PSU to give it that extra flare.  Over the last year I have seen several cases with PSU mods added and I have done a few myself.

This guide will demonstrate how to change PSU fans add a PSU window and add more ventilation to your PSU for cooling and sound purposes.

   Materials

• replacement fan 70 or 80mm depending on the PSU
• small sheet of clear plastic for the window about 3"x5"
• wires / solder
• led for lighting
• heat shrink
• silicon sealant or other good adhesive

   Tools

• Dremel, nibbler or some other cutting tool
• soldering iron
• Philips screwdriver

   Step One: Opening up the PSU

   Most PSUs are built in about the same way, they have a base housing piece onto which the circuit board and fan are attached, and an outer housing that covers the circuitry inside. To open up the case simply unscrew the cover and remove it. Remember there can still be some stored energy in the PSU capacitors so it would be best to leave the PSU unplugged for a while before you open it up.

   Here you can see the placement of the four screws that hold the PSU together:

   What the PSU looks like open:

   Step Two: Replacing the Fan

   Once the cover is off of the PSU it is easy to remove the PSU fan to exchange it with a quieter one. Simply unscrew it from the back of the PSU and cut the wires attaching it to the main board. Then just solder the leads from the main board onto the leads of your new fan and bolt it into place. During this process you can also chose to run fanbus controls to your PSU fan in order to help further decrease the noise.

   A closeup of how the fan is placed inside:

   When I wired in the new fan i also added an LED in parallel to add some light to the inside of the power supply: