The ideal case for me is:
* Stackable. Sounds obvious, but look how few cases acutally are designed for this.
* No connectors but on the front. This includes the ATX panel as well as power and all others.
* Small. But still offering full-size slots.
* Little "design". No colorful glowing bullshit. (Think minimalistic.)
* Cheap. Again, no frills.
Who knows such a case? Who would like to have one?
