I've contributed to the following products/projects to a greater or lesser extent:
My job included working on https://github.com/facebookexperimental/eden/tree/master/eden/mononoke and https://github.com/facebookexperimental/rust-shed
Fixes to various rust crates
QuickFIX is a library providing a Financial Information eXchange (FIX) engine for connecting to markets such as NYSE, Euronext and others. In the course of my work at Anvil I provided a number of feature enhancements to version 1.5 which was released in May 2003.
Automake is a software build tool. I contributed functionality useful for parallel builds of projects using CORBA IDL and other "Built Sources".
TAO is the "The ACE ORB", an open source CORBA request broker with good standards compliance and performance.
unixODBC provides database connectivity on UNIX platforms. I contributed portability fixes for HP-UX and Sun Solaris.
A free C++ version of JDBC v2 over ODBC. This is much easier to use than the ODBC C API. I contributed fixes to storage of binary large objects and managed the 0.2.3 release.
A fine perl CORBA binding. I provided the test suite and some bug fixes.
You can probably still find on CPAN ssltunnel.pl , a firewall tunnelling script for accessing external network resources through a normal web proxy. You can use this to access SSH, CVS hosts and many other TCP/IP based services from behind a firewall.
Other projects I used and followed, but haven't submitted code to include:
An excellent C and C++ compiler, I'm interested in the C++ implementation from the point of view of features, portabilty and compile time speed.
JBoss is a excellent free Java J2EE application server. Don't spend any money on websphere before you've give JBoss a try.
Libtool is an very useful tool to portably build shared libraries.
Plus many more...