FaceDeer

Airtanks

Provides pressurized air tanks for extended underwater excursions

Anvil

Hammer and anvil for repairing tools

Breadcrumbs

Path marker signs for use when exploring a twisty maze of passages that are all alike.

Castle Farming

Contains farming products useful for decorating a castle

Castle Gates

This is a mod all about creating castle gates and dungeons

Castle Lighting

This mod contains medieval castle lighting solutions

Castle Masonry

This is a mod all about creating castles and castle dungeons.

Castle Shields

Adds decorative wall shields

Castle Tapestries

This is a mod for creating medieval tapestries, as found in castles

Castle Weapons

Provides several medieval weapons for use around castles

Commodity market

Provides API support for various in-world commodity markets

Crafting Bench

An auto-crafting bench

Death Compass

A compass that points to the last place you died

Digtron

Adds components for building modular tunnel boring machines

Dwarf Fortress style caverns

Adds vast underground caverns in the style of Dwarf Fortress, complete with underground flora in diverse biomes.

Dynamic Liquid

Flowing dynamic liquids and ocean-maintenance springs.

Fantasy Commodity Markets

Adds a number of fantasy-themed marketplaces using commoditymarket

Footprints

Players walking over various types of terrain will leave footprints, and optionally pack the soil down into trails

Global Bulletin Boards

Allows creation of global bulletin boards where players can post public messages

Hopper

Adds hoppers to transport items between chests/furnace etc.

Magma Conduits

Removes default mapgen lava and adds widely-spaced vertical lava "veins".

Named Waypoints

A library for managing waypoints shown in player HUDs that can be discovered by exploration.

Name Generator

A lua library for generating random names based off of rulesets and syllable lists.

Orbs Of Time

A mod containing magical orbs a player can use a limited number of times to change the time of day

Personal Log

A personal log where players can track events and places

Pontoons

A "floating" block that can be placed at the surface of a body of water without needing to build pilings first.

Radiant Damage

A mod that allows nodes to damage players at a distance

Ropes

Adds rope boxes of various lengths and also rope ladders.

Sounding Line

A tool for determining the depth of water or the depth of a hole.

Warning: Non-free media.

Subterrane

A mod that creates vast underground caverns and allows biomes to be defined for them

Torch Bomb

Place torches throughout your entire surroundings with a torch bomb