We're long time fans of the Amiga franchise here at Tom's Hardware and can't ignore our biases when it comes to awesome Raspberry Pi crossover projects—like this HDMI hack for the Amiga 500, created by a maker known as Reinhard Grafl.
The project essentially uses a Raspberry Pi to work with an adapter board to convert the Amiga video signal into HDMI output. It's designed to work with Amiga versions that use a socketed DIP Denise chip.
The project requires a small form factor but not much processing power, making the Pi Zero model an optimal candidate. It uses an application called RGBtoHDMI which is open-source and available on GitHub.
You can find a four-part video series following the project on Grafl's YouTube channel. The adapter board is open-source with schematics available for download on the project Github page. Grafl is also offering a few pre-made units for sale. Check out the project page for details on how to order one.
Be sure to visit our list of Best Raspberry Pi Projects if you want to see more cool Pi creations from the maker community, and yes, a couple of them are Amiga-themed.