Releases
These are sources and clients from all different protocols released by the owners/developers. I can't stress enough how useful all of these are to the industry. I learned everything I know from reading code so please spend some time and take a look through as many as you can.
Clients
Devious Client (OSRS)
A maintained, non-compliant, open source fork of OpenOSRS and Unethicalite with small modifications
Sources
Kronos 184 (OSRS)
A semi-custom OSRS from Patrity, ReverendDread, RSPSi & more that I have learned so much from
OS-Scape 171 (OSRS)
A massively popular server created by Velocity, Situations & more bought & released by Spooky
Apollo (317)
Apollo is a high-performance, modular RuneScape emulator with a collection of utilities for managing data files and plugins
Elvarg (317)
A base platform developed by Professor Oak with a ton of core rework packed with OSRS data
2006scape (317)
2006scape is an open source RuneScape game server emulator (2006) maintained by the community
2009scape (530)
2009scape is an open source RuneScape game server emulator (2009) maintained by the community
2011scape (667)
2011scape is derived from RSMod v1 converted to work with the RuneTek-5 engine started by .alycia