ElectricalFire
FAQ - Jikes Compiler Open Source Project
GCJ - front end to GCC which can natively compile both Java source and bytecode files.
Glass - a classical static compiler implemented as a .class (java bytecode) frontend of gcc
Harissa - a Java environment that includes a compiler from Java bytecode to C and a Java interpreter.
J Accelerator
Jikes - a compiler from Java source code to bytecode.
shuJIT - Just In Time compiler for Sun JVM/x86.
Toba - A Java-to-C translator.
TowerJ - Native deployment compiler and runtime environment for server-side Java.