Atari800 is an Atari 8-bit computer (400, 800, and XL and XE series) and Atari 5200 game system emulator for DOS, Windows, Amiga, Atari ST, Mac, and Linux/UNIX. It includes support for Atari cartridge ROMs, popular Atari disk images files, running Atari binaries directly from the host system, and accessing the host filesystem from within the emulated Atari.
The Free Unix Spectrum Emulator (Fuse) is an emulator of the 1980s home computer and various clones. It emulates the Spectrum 16K, 48K, 128K, +2, +2A, +3, +3e, and SE, the Timex TC2048 and TC2068, the Pentagon, and the Scorpion. Almost all the common Spectrum emulator file formats are supported, including .rzx input recordings, .tzx tape images, and .szx and .z80 snapshots.
MDK (MIX Development Kit) provides tools for developing and executing, in a MIX virtual machine, MIXAL programs. The MIX is Donald Knuth's mythical computer, described in the first volume of The Art of Computer Programming, which is programmed using MIXAL, the MIX assembly language. MDK includes a MIXAL assembler (mixasm), a MIX virtual machine (mixvm) with a command line interface, a Guile-based virtual machine (mixguile), a GTK+ based GUI (gmixvm), and a mixvm-Emacs interface (mixvm.el). MDK utilities are extensible using Scheme.
The Machine Emulator, or tme, provides a general-purpose framework for computer emulation. The goal is to create a large library of modules, each emulating a specific computer chip, bus, board, etc. These modules offer standard interfaces that allow you to connect them together to create a whole machine emulation with a minimum of effort. It is possible to emulate a Sun 2/120 and a 3/150, both with NetBSD, and a SparcStation 2 with NetBSD or SunOS 4.1.4 (aka Solaris 1.1.2).
TinySID is a very small SID player. Current features include 99% 6510 CPU emulation and fat 6581 SID emulation including filters (which sound different to other players). It has nothing to do with other projects such as SIDPlay, and the 6510/6581 emulation is based on routines by Tammo Hinrichs that have been further developed.
Wine is an implementation of the Windows API on top of X and Unix. It does not require Microsoft Windows, but can use native Windows DLLs if they are available. It provides both a development toolkit for porting Windows source code to Unix as well as a program loader, allowing many unmodified Windows programs to run on x86-based Unixes.