+65535. For me, the killer use case for my Raspberry Pi (even the original one, or just any single-board computer to be honest) is always an emergency chip prog

+65535. For me, the killer use case for my Raspberry Pi (even the original one, or just any single-board computer to be honest) is always an emergency chip programmer. When working with embedded systems, from time to time you need to program firmware into a variety of chips - parallel EEPROMs, SPI EEPROMs, I2C EEPROMs, AVR microcontrollers, PIC microcontrollers, STM32 microcontrollers... Traditionally, many tasks require vendor-specific tools. It's incredible frustrating when you want a chip programmed today but don't have the right programmer at hand. Thanks to Raspberry Pi's GPIO, you can get bitbanging software programmers for a large number of chip protocols. The parallel and serial ports on a PC used to serve the same purpose. But many modern systems don't have them. You can use USB converters, but latency is usually terrible due to USB overhead. The 3.3 V logic on the Raspberry Pi is also easier to use than 5 V TTL level or 12 V RS-232 logic level.