For this project I needed the following things:
The goal for this cabinet was to cycle air through without generating too much noise or changing the visual aesthetic of the cabinet. In order to do this, I mounted two fans in the bottom of the cabinet, one pulling air in and the other pushing air out. This way there would be a continuous flow of air through the cabinet to exhaust the hot air being generated by the components. Also, because they were mounted in the bottom, the fans are never visible.
In this particular case, the fact that Ikea furniture is cheaply made turned out to be a good thing. Not quite sure of what to expect I cut a big hole in the area that I wanted to place the first fan. The result was a nice hollow cavity where I could mount the fan without it protruding from either side.
After cutting out the hole, I mounted the fan with screws to the inside surface of the cabinet.
This was followed by a silver fan screen to make sure nothing fell into the fan from inside the cabinet as well as to hide the fan when the doors are open
Finally, everything was put back into place you would never know that the fans were even in there. At 8.7 dBa they can run all the time without being heard and you don't have to worry about your components overheating.