Collectible Skins
Zughy

Wear and unlock skins

Dungeon loot chests
X-DE

Adds loot chests, a command to prevent spawning loot in the chest so you can save a schematic with a loot chest, adds 2 functions to create loot in other chests

Guns4dWorkbench
Jo5629_

Craft guns and their components with an added workbench.

In the Fog
Jo5629_

Herobrine has entered your world.

Power Rangers Modpack
LC Creations

Adds power rangers and an API to create your own.

Configuration Panel
sorcerykid

API extension that allows seamless loading of mod configuration at runtime

Beds Redux
sorcerykid

A complete rewrite of the Beds mod with many additional features

Item Holders
Jose_ManuelS18

Adds 'Item Holders', blocks that hold your items in display, also provides a API.

Mesecons Stealthnodes
Clyde

Register your own Ghoststones.

Noriel Sylvire's Minerals Core Modpack
Noriel_Sylvire

An API for automatically registering recipes, nodes and ore generation.

Library Mount
Panquesito7

API Framework for mounting objects.

Scripted World Editor
Neuromancer

API that allows you pass in scripting tables to fill a series of shapes of different sizes with different nodes