I have a laptop, an Itronix IX250. It's one of those fully ruggedised water and shockproof ones you don't need a laptop bag for.
It is, however, one of the older models, not having built-in WiFi, so to utilize this facility, it needs an expansion card.
It has two Cardbus slots. The one on the left side is of conventional depth, and a WiFi card sticks out of the slot (as it's designed to do), but this would leaves it prone to damage if left in place, and also leaves the laptops internals unsealed, and the slot cover flapping.
The righthand slot is much deeper. It's designed to take a GSM phone card internally, which connects to an external aerial.
You can fit a WiFi card in this slot also, and it doesn't protrude, but unfortunately, being encased in magnesium alloy does seem to have an adverse effect on signal strength.
The solution? Wire the card to an external aerial!
The problem is that the existing aerial is designed for 800-900MHz cellphone signals, not 2.4GHz WiFi. Reports are that it doesn't work very well, and that the cards tend to stop working after a while.
( Images cut for explicit technology abuse )