L4

DROPS - The Dresden Realtime Operating System Project - L4 and Linux based research project aiming at the support of applications with Quality of Service requirements. At TU Dresden.
os.inf.tu-dresden.de/drops/overview.html

E1 - A distributed operating system based on the concepts of object replication, component model support and persistence. It consists of a L4 microkernel and a set of distributed objects acting at the user level. [Open source]
www.e1os.org/

Fiasco - Preemptible, realtime, 2nd-generation microkernel, fast, maintainable, readable, supports hard priorities, uses non-blocking synchronization for kernel objects to guarantee priority inheritance, ensure runnable high-priority processes never block waiting for lower ones; rework of L4 interface. [Open Source, GPL]
os.inf.tu-dresden.de/fiasco/

The Hurd on L4 - Porting the Hurd to the L4 microkernel. News, plans, pointers to mailing lists and websites.
www.nongnu.org/l4hurd/

L4 Microkernel - L4/MIPS: stable L4 for MIPS R4x00 processor, may be fastest kernel for this architecture. L4/Alpha: begun at Technical University of Dresden, SMP version released. Linux ports: L4/MIPS, L4/Alpha underway.
www.cse.unsw.edu.au/~disy/L4/

L4 Microkernel Family - Growing article, with links to many related topics. Wikipedia.
en.wikipedia.org/wiki/L4_microkernel_family

L4/Darwin: Darbat - Experimental port of Darwin to L4 to study traits of large-scale microkernel-based system; has port of IOKit to L4, modified libc to communicate to Darbat Server, XNU with many machine-dependent parts highly modified. National ICT Australia.
ertos.nicta.com.au/software/darbat/

L4Ka Project - L4-based microkernel systems, for embedded systems to huge servers; Pistachio kernel. L4: tiny, fast, 2nd generation microkernel using hierarchical external pagers and guarded page tables. Goals: create, prove, establish new methodology for systems that helps manage growing complexity, minimize legacy dependence.
l4ka.org/

Mungi - Orthogonally persistent, capability-based secure SASOS using L4 2nd generation microkernel. Goals: Prove SASOSs can run on normal hardware, be as secure as normal OSs; can be as efficient as, and are faster than, normal OSs in some important uses; can be pure SASOSs with all data (even system data) in one address space and no other IPC mechanism is supported by OS. POSIX emulating. [Open Source, GPL]
www.cse.unsw.edu.au/~disy/Mungi/

Perseus - A secure platform for applications that use digital signatures. Based on L4 and Linux. Research project at Applied Data Security Group, Ruhr-University Bochum., Germany.
www.perseus-os.org/

SawMill: A Highly-Configurable Operating System - Goal: address the complexity of building and maintaining a variety of custom OSs. As embedded and personal systems grow more common, the need to make OSs customized to many device and application needs rises. At IBM T.J. Watson Research Center.
researchweb.watson.ibm.com/sawmill/

SourceForge: L4Ka Microkernel - The L4Ka microkernel is an L4 compatible kernel running on many platforms: ARM; MIPS; 68k, PPC; x86. A port of Linux atop an L4Ka microkernel exists.
sourceforge.net/projects/l4ka/

Virtualised OS: Wombat - Experimental port of Linux to run on L4/Iguana; is not intended to be standalone, best used as part of Iguana project. National ICT Australia.
ertos.nicta.com.au/software/kenge/wombat/latest/