Aquamarine
RasPiManiac

Adds Aquamarine ore, ingots, etc.

Useful Contraptions
theFox

Some useful contraptions / machines.

sfinv++
swagtoy

Improves the inventory, and fixes some formspecs throughout some mods.

Quartz Geodes
AwesomeDragon97

Extends the Geodes mod with quartz geodes.

Mesecon Register Circuits
marek

Adds Latch and Flipflop circuits.

3D Armor Mobile
LandarVargan

Adds a command to bring up a formspec that allows mobile users to put on armor

Castle Storage
FaceDeer

Contains storage containers one might find contained in a castle.

Blox
mt-mods

Adds lots of differently colored and textured blocks to Minetest.

doorbell
Miniontoby

A doorbell mod with sound

Lava + Water > Stone
1F616EMO

Cool Lava into technically special stones for easier cleanup

X Clay
SaKeL

Adds hardened clay.

World Borders
argyle

Add impenetrable barriers to the sides and bottom of the world.

Hard Trees
octacian

Require tools to break trees and introduce beginner-tier rock tools.

Loot
Byakuren

A loot framework.

Startest
Robot10&Scheletor

This mod adds several space stuff to the game.

Alien Tools
chaosomnium

Alien Tools Mod for Minetest - adds Alien Tool, Shield, biome, etc

Ice Machine
cheapie

A machine that makes ice cubes.

Candy
Kostivar

Adds candy which you can make from candy ores.

Technic use Battery
1F616EMO

Use energy from RE batteries in the inventory

Assets_Warehousepart2
JALdMIC

Part 2 of Assets_Warehouse

Rotting Wood
Polynium

Causes wood to slowly rot while exposed to water

Cube Mobs
Xanthus

Adds various cube mobs with different abilities using mobkit.

Waste
Jolesh

Adds Waste and ways to recycle it into useful resources

Slot Machine Mini-games
mt-mods

Provides an "engine" to drive simple slot machines (includes two). Spins reels, takes in/pays out in Minegeld (Dan's currency mod), etc.

Uncrafter
JoeEnderman

Adds an uncrafting table

Leather Armor
X17

Adds an armor made of leather

Throwable Snowball
ComputeGraphics

Adds a throwable Snowball

Rainbow Source
Shara

Adds coloured water.

obsidian
GigaByte

more uses for obsidian

Pink Lava
TenPlus1

Adds pink lava to certain depth of map with new mahogany obsidian block

Mesecons Microphone
Maverick2797

Chat-toggleable mesecons node.

Shadow Realm
archfan7411

The realm of shadows contains many hidden horrors.

Coins
Clyde

Adds 3 kind of Coins to your game

Movement Essentials
Daniel

Adds umbrella for slow fall (hang gliders), consume mese crystal to recall (return to spawn), and throw fragments to teleport.

Saphire
Ryft77

Adds saphire stuff

Mese Restriction
mt-mods

Minetest mod: restrict mesecons use to priv

More Ladders
SkyBuilder1717

Adds more ladders and sticks!!!

Trucraft
mt-mods

An alternative crafting system done entirely in the world.

Fake Fire
Semmett9

Fake fire adds in a block that looks like fire, but dose not have the risk of burning down your creations.

French Toast!
RasPiManiac

Adds French Toast. That's it.