The goals of the JSMachines Project are to create fast, full-featured simulations of classic computer hardware, help people understand how these early machines worked, make it easy to experiment with different machine configurations, and provide a platform for running and analyzing old computer software.
The above simulation features an Intel 8088 running at 4.77Mhz, with 64Kb of RAM and an IBM Monochrome Display Adapter. For more control, there are also Control Panel and Soft Keyboard configurations, featuring the built-in PCjs Debugger. For even greater control, build your own PC! The PCjs Documentation has everything you need to know (well, it's a start anyway).
Some pre-configured machines are shown below, ready to run BASIC, DOS, Windows 1.01, and assorted non-DOS software.
Below is the OSI Challenger C1P, another simulation in the JSMachines Project. It simulates Ohio Scientific's 6502-based microcomputer, released in 1978. More details about this simulation and the original machine are available in the C1Pjs Documentation.