Simple RTJ
- Clean-room implementation of the Java Virtual Machine that has been specifically designed to run on devices with a small amount of system memory (from as low as 48KB). [Commercial]
- http://www.rtjcom.com/

Javac on EPOC
- Instructions for compiling Java programs on EPOC.
- http://www.hasiland.com/javaonepoc/javac.html

Introduction to EPOC Java Development
- Article covering the differences between ordinary Java development and EPOC Java development, such as designing for a smaller screen, lower resources and special deployment.
- http://www.wirelessdevnet.com/channels/pda/training/epocjava1.html

Taurus Java VM
- Available for Psion Series 3, MS-DOS and Linux. [Commercial]
- http://www.tsac.co.uk/javavm/

JOP: a Java Optimized Processor
- Implementation of the Java VM as soft processor core in an FPGA for embedded real-time systems. [Free for personal use or for educational purpose]
- http://www.jopdesign.com/

Ewe
- PocketPC and Palm Java Virtual Machine.
- http://www.ewesoft.com/

JControl
- A Java platform optimized for measurement, control and automation applications. The JControl Virtual Machine's design is as lean as it runs even on 8-bit microprocessors and hence it can compete with common 8-bit-systems.
- http://www.jcontrol.org/

Snijder Micro Systems
- Offers embedded controller with online demonstration and development kit.
- http://www.embedded-web.com/

Waba
- Small Java virtual machine aimed at portable devices, but also runnable on desktop computers. [Open source, GPL]
- http://waba.sourceforge.net/

DCT Ltd
- Provide custom solutions for embedded Java with their Lightfoot technology.
- http://www.dctl.com/

Compiling Java on your Psion 5mx
- Instructions for how to turn the Psion Java environment into a system capable of compiling Java programs.
- http://www.davies.lu/Java/

TinyVM
- Very small Java VM, and firmware replacement for Lego Mindstorms RCX. Progenitor of leJOS. [Open Source, MPL]
- http://tinyvm.sourceforge.net/

Skelmir
- Specializes in Java virtual machine and compilation technologies for the embedded device communities.
- http://www.skelmir.com/

NewMonics PERC
- Virtual machine and development tools for embedded platforms, including static linking and native compiling, and a real-time garbage collector. [Commercial]
- http://www.newmonics.com/perc/info.shtml

leJOS
- Java based OS for Lego Mindstorms RCX. [Open Source]
- http://lejos.sourceforge.net/