The Transmeta Crusoe was perhaps the most creatively engineered processor available around the new millenium. Rather than directly implement a particular instruction set, the Crusoe used a software abstraction layer called "Code Morphing Software" to translate guest software instructions into native instructions on the Crusoe. While this was only commercially used for x86 compatibility, the Crusoe was demonstrated running Java bytecode directly.
The Crusoe also had the benefit of having lower power consumption and running cooler than contemporary Intel and AMD CPUs, which made it popular for notebook and ultra mobile PCs. It was used in the Compaq TC1000, Toshiba Libretto L-series, and OQO Model 01, among others. The 128-bit Crusoe was replaced with the Efficeon in 2004, though the company pivoted away from designing CPUs shortly thereafter. Transmeta's influence can still be felt in newer products, as their power management techniques were licensed to NVIDIA, among others.