Sometimes the console itself has had its day, but a few pieces are still useful: the controllers, the hard drive and the cables.
The DualShock 4 from the PS4 is the star. It connects to phones, tablets and PCs, and even works with some newer consoles. You can pair it with an Amazon Fire TV Stick for cloud gaming or as a stand-in remote. The older DualShock 3 from the PS3 does some of the same, but it works with fewer devices and is fiddlier to connect.
The hard drive is a bigger prize. Sony built PlayStation drives to be swapped by owners, so getting one out mostly means removing a few screws. Reformat it, drop it into a USB enclosure, and you have external storage for a laptop or another console. Keep the HDMI and power cables too, then recycle what is left.