PiStorm is an adaptor board that plugs into the socket for the Amiga's Motorola 68000, 7.16 MHz CPU. Upgrading the A500+ to a 68EC030 CPU running at 70 - 80 MHz. At the time that would've been a dream setup requiring a much more expensive machine, the A4000 and a huge injection of cash for third party accessories.
PiStorm is designed to use a Raspberry Pi 3 A+ which functions in place of the CPU and according to Schwarz, there are plans in the works for a CM4 edition which could see a greater increase in performance. Other features provided by PiStorm are support for large amounts of RAM (up to 128MB), virtual SCSI devices, swappable Kickstart ROM images (the BIOS of an Amiga) and accelerated high resolution graphics via the Raspberry Pi's HDMI port.