SLUDGE has always been great. But now, it's also a programming language. SLUDGE (standing for Scripting Language for Unhindered Development of a Gaming Environment) is a system by which anyone (within reason) can make an adventure game. It runs in any recent version of Windows including XP, 98, 95 and NT and also, through the wonder of emulation, pretty darned well on Linux. It's high-res and uses 16-bit colour. For more information, see the FAQ.
To make your own SLUDGE games you'll be needing the SLUDGE development kit and then to play SLUDGE games on your machine you'll require the SLUDGE engine.