Over time since initial release, many users have worked hard to improve the game experience or Rebirth through feature addition and/or fixes. This page tries to keep a record of player work that either overtly or coincidentally became incorporated into X Rebirth over time.
Thinking back over almost 2 years means this list won't be exhaustive but it can be easily updated. The list is chronological by patch from Egosoft that addressed the theme.
Please note that the following mods/extensions are generally not recommended since they are mostly redundant for the reason they are listed. Hyperlinks are basically added to serve as monuments 
v3.60: Clean Sidebar and Main Menu by Olympian: Removed striped backgrounds ("scan line effect") to aid readability.
v3.60: Realistic physics and full/assisted inertia by Realspace: Added ability to rotate 180o to fly backwards (amongst other things).
v3.60: OOZ ship building by ubuntufreakdragon: Did what it says on the tin - OOZ Ship Dealers became accessible via the map.
v3.50: Engineer Drone Fix by w.evans: Fixed an issue whereby docked Construction URVs were not being marked as available.
v3.50: Manager Fix by ubuntufreakdragon: Improved the way a Manager determined what a station needs, helping it to produce.
v3.50: SMUPS by w.evans: Added mining, construction & cargo drones to plot URV Forge (as of 3.60, still makes additional changes).
v3.20: Marine Rebalance (by w.evans) and Boarding Options (by camus/Clownmug): Added info on boarding attack strength (as of 3.60, still makes additional changes).
v3.00: Recall Player Drones by YorrickVander: This mod allowed us to order the Skunk's drones to dock back up.
v3.00: Remove spawned trade ship wares by SilverXarrow: Prevented trader spawning full of wares to improve the game economy.
v2.50: Albion Civil (by Reaperxvii) and Real War (by IRaven): Added "civil war" behaviour between Plutarch and Heart of Albion+Canterans.
v2.50: Build Small Ships by Berserk Knight: Added the ability for medium shipyards to build small and medium ships.
v2.50: Core_shields by bobucles: Added shields to the hulls of capital ships.
v2.50: Targeting UI Extension by Observe: Added an external camera.
v2.50: Universal Menu System by Berserk Knight: Added additional slots to the radial menu in the era before we gained the sidebar.
v2.00: Never Enter Stations Again by Mad_Joker: "a major source of inspiration for our version of the functionality to allow most tasks to be performed without landing on stations" (CBJ, 20.05.2014).
v1.24: Targeting UI Extension by Observe: Added targetting functions such as for nearest enemy.
08.12.2013: Build in Maelstrom by csfelfoldi: Added station build locations to Sigma Sector when none were none were thought to exist.
What other work could we add?