I've done something moderately stupid. We've got a neat little machine to do some networking gubbins on our project. I recently ordered one. It comes without memory or hard disk, so I ordered those too.
The hard drive on the purchase order was out of stock, so Purchasing came to me with an alternative. I was in the middle of talking to someone, so I had a quick look (suitable size, 2.5", not much more expensive) and approved it.
The boxen are actually shipped from Germany (no reputable UK supplier), so the hard drive and memory arrived and sat for a week. The main box arrived today and I started assembling. I got up to the hard drive.
The alternative hard drive is SATA. The box is PATA only.
Just ordered another, PATA, drive for next day delivery....