Badlands
AwesomeDragon97

Adds the badlands biome, which contains plentiful clay and gold.

Uranium Stuff
Epoxum

Adds Uranium tools and armor, compatible with technic.

Fireflies
Shara

Adds fireflies which can be caught in a net and placed in bottles for lighting.

Void Chest
MeseCraft

Access your belongings anywhere by using the power of the void chest!

Biospheres
Feufochmar

A map generator generating single-biome islands inside glass spheres.

Darkage - the original plus improvements
addi

DarkAge adds several new nodes and crafts to create a pre industrial landscape.

Advtrains Train Rocket
AdvT. Supplemental

A model Stephenson's rocket and some barrel wagons

Deepslate
Silver Sandstone

Adds deepslate and related building materials.

Stripped Trees
1faco

Adds Stripped tree trunks.

Horror: Rescared
SkyBuilder1717

Fork of TX_Miner's Horror mod, but heavy modified with adding a lot of additional stuff.

Geodes
AwesomeDragon97

Adds amethyst geodes and an API for making custom geodes.

Inventory Bags
cx384

Adds bags

Magma Conduits
FaceDeer

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

Wet Mud
Nicu

Hydrates farmland without using water directly

block physics
GigaByte

Add pieces of broken blocks when breaking them.

Scaffolding
Semmett9

Adds wooden and Iron scaffolding.

Angled Walls
TumeniNodes

Angled & Sloped Walls, Angled Glass, & Angled Doors

MOAR! ARMOUR!
Duvalon

Additional armours to build and wear

boomstick
fluxionary

a tool for testing the behavior of tnt

NextGen Bedrock
StarNinjas

Adds an indestructible bedrock layer at the bottom of the world.

Minimap Radar
OgelGames

A simple mod that enables the use of the minimap radar with a craftable item

Minertrade
Lunovox

It adds various types of money, exchange table, Dispensing Machines, ATMs in stores.

Nettles and Other Weeds
Hypernoot

Nettles spawning on junky plots

Pigiron
TenPlus1

Adds pig iron ingots which need to be crafted to make steel, also blocks and stairs.

Fire Master
Flay Krunegan

Fire Master is a powerful weapon that can shoot fire

Colored Meselamps
devurandom

Adds colored versions of meselamps, craftable with dyes

Turret
GigaByte

adds a defensive turret

Flight
Amaz

Adds three different methods of flying, wings, jetpacks and flying carpets.

GloopTest Pack
GloopMaster

Adds ores, tools, types of glass, a table to the game.

Modern Ish
thomasthespacefox

A collection of modern-ish odds and ends.

Sieves
AwesomeDragon97

Adds sieves that are used to separate (occasionally) valuable debris from sand.

Coloredwood
mt-mods

Colorize some wood!

Music Player
Jose_ManuelS18

Adds a music player and discs

Portable Chests
Bob64

Portable chests you can pick up even when there are items inside.

Mobs Takodachi
Silver Sandstone

Adds takodachis.

Quarry Mechanics
kestral

Adds quarry mechanics to stone nodes.

More Pickaxes
Koda_

Adds additional pickaxes to the game

Moonflower
TenPlus1

Moon Flower, when touched by the moon, it opens up a casting light.

Inventory Plus
TenPlus1

Simple Inventory replacement

Gemstones
Koda_

Adds Gemstones to the game