This past Halloween, Alan Cox announced Fuzix OS, a project for building a UNIX-like operating system for 8 bit computers, based on UZI sources. This OS targets a number of physical machines, both old and homebrew computers, and some emulators too. The easiest and more approachable way for trying Fuzix OS is running it on cpmsim, which comes bundled inside the Z80pack package. If want to give it a try the easy way, just continue reading.
UPDATE: Mikolas has added support for the DE2-70 board. Check his repo here: https://github.com/mikolas/socz80-de0_nano Due to my intrinsic, chronic curiosity, for a long time I wanted to get a in touch with FPGA and related technologies (Verilog, VHDL, etc…), and experience the feeling of total control, having both hardware and software subdued to my control (well, not so much, due to the mysterious and semi-secret process of synthetization and fitting done by the tools involved in the process, but you get the idea).