Before the Raspberry Pi came out, one cheap and easy way to get GPIO on a computer with a real operating system was to manipulate the pins on an old parallel port, then most commonly used for print…
The PSU isn’t just for the PI, but you’d not know that from the article which seems to have been written by someone with literally no imagination. If you’re looking for a setup that lets you use a RasPi as, say, a file server with a fibre channel card, or a media hub with a GPU that can transcode several streams at once, then it’s a really neat product and that justifies a decent PSU.
The PSU isn’t just for the PI, but you’d not know that from the article which seems to have been written by someone with literally no imagination. If you’re looking for a setup that lets you use a RasPi as, say, a file server with a fibre channel card, or a media hub with a GPU that can transcode several streams at once, then it’s a really neat product and that justifies a decent PSU.