Open Source Server Plugin List
Known Open Source Plugins
Use this page to find an open source plugin, or list info about your open source plugin to help other coders new to the SDK and programming server plugins.
Valve Server Plugins
This is a list of known open source Valve Server Plugins (VSPs). Plugins with released source code are hard to find, so it should help everyone if a list of plugins with available source code are posted here.
Warning: Please check the license of the following programs before reusing any code as they may not be true open source.
Description: Advanced admin plugin.
Features: Advance admin plugin including menus, kick, ban, reserved slots, advanced effects, etc.
Description: As you kill your opponents, you gain Experience. Eventually when you have reached your experience quota, you gain a new Level. This means you can buy Upgrades which give you an advantage over your opponent.
Features: Advanced effects including such things as long jump module, invisibility, health regeneration, fire grenades, etc.
Metamod: Source Plugins
Metamod: Source (MMS) provides methods of interacting with the server that cannot be easily accomplished using the standard VSP interface. If you will be attempting any advanced concepts that are not provided for in the VSP interface, it is recommended that you use MMS. Not only does it easily allow things like editing damage to players that is very difficult in VSP plugins, it also manages the hooks so that your plugin doesn't interfere with other plugins and crash the server if they hook the same functions.
Description: This CS:S plugin has everything! From vehicles in CS:S to modified zombie gameplay, and tons of other stuff. Not for the faint of heart, but if you're an advanced programmer, you'll find some interesting stuff here. NOTE: THIS PROGRAM WAS ABANDONED AND MUCH OF WHAT IT DOES PROBABLY DOESN'T WORK WITH CURRENT UPDATES.
Features: Everything from admin functions to vehicles in CS:S to zombies.
Website: This is a backup link. 
Description: Server-Side Anti-Cheat Plugin for Counter Strike Source / Global Offensive / Promod
Features: Detecting some ConVar violation, Aimbots, TriggerBots & Autopistol, BunnyHop and more ...
Website: NoCheatZ @ GitHub
License: Apache 2.0
Author: Chris Deegan/Peter Rendle
Description: CS:S Zombification!
Features: Respawning zombies, zombie decapitation, concussion grenades, anti-camp, swear filter, stats, discrete zombie control and much more!