Crusoe
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Crusoe is a family of x86-compatible microprocessors from Transmeta. They use a software abstraction layer, or virtual machine, known as the Code Morphing Software (CMS), running on a VLIW hardware "core". CMS is the only application written for the native VLIW architecture, and translates the incoming x86 instruction stream into VLIW instructions.
In theory, it's possible for CMS to be modified to handle other instruction streams (i.e. to emulate other microprocessors), but this is not likely to happen anytime soon, since it is probable that the current hardware has been optimized for x86.
The addition of an abstraction layer between the x86 instruction stream and the hardware means that the hardware architecture can change without breaking x86-compatibility, just by modifying CMS. For example Efficeon, the second-generation Crusoe, has a 256-bit-wide VLIW core versus 128-bit in the first generation.
Crusoe performs in software some of the functionality traditionally implemented in hardware (e.g. instruction re-ordering), resulting in simpler hardware with fewer transistors. The relative simplicity of the hardware means that Crusoe consumes less power (and therefore generates less heat) than other x86-compatible microprocessors running at the same frequency.
The name is taken from the novel Robinson Crusoe.
