An SDK for developing DOS software for x86 machines, including IBM PC compatibles and NEC PC-98.
Since a PC is composed of a number of off-the-shelf chips, the SDK is structured in a way to reflect this. This means that the definitions related to specific chips such as the 6845, the 8253, 8259 etc. are separated from how they are implemented in the PC architecture (the IO addresses, memory addresses, IRQ and other resources they use). A header file for a specific chip will only contain the generic information for the chip. A separate system-specific header file (in this case IBMPC.inc/IBMPC.h or PC98.inc/PC98.h) will then contain the information specific to the implementation of that system. This allows you to use the header file for the chip for any system that implements it. This is especially useful for writing code for both IBM PC and NEC PC-98, which mostly use the same hardware, but not at the same locations. In future, it may also be expanded to other systems, such as the Tandy 2000.
A collection of cartridges, adapters and replacements for the Commodore C64.
On My abandonware you can download all the old video games from 1978 to 2010 for free! You can play Pacman, Arkanoid, Tetris, Galaxian, Alter Ego, or Blackthorne, Civilization, Sim City, Prince of Persia, Xenon 2, King's quest, Ultima, Kyrandia, The Incredible Machine, Another World, Test Drive, Flashback, Lemmings!
And more, of course.
A 100% compatible replica of the famed SB 1.0 sound card. 8-bit ISA card. Full bill of parts. Even has a hex dump which turns an Atmel 89S51 into an 80C51 DSP chip (if you don't feel like buying one from China).
An application which downloads and archives Windows Updates for offline installation or slipstreaming.
A website that lets you search out and download missing .dll files to fix a botched reinstall or application upgrade.
The website for a classic space trading/warfare game called Elite run by one of the original authors. Includes a lot of information and even the novella which was published with the original version.
A technical reference site that has lots of odd information, most of it PC related. Data formats, file extensions, datastructures and algorithms of sundry kinds and uses, hardware specs, microcontrollers, history, advice... there's a lot of stuff buried in here. If you need something you could do worse than check here first.