The Rancraft Penguins Mod is quite an interesting one that adds 17 different penguin species to the game.

If you’ve ever thought that Minecraft lacked in polar animals, then this mod is for you. The penguins vary in size and can all be tamed with raw fish. When tamed they don a red bow tie.

The penguins will spawn in a few different biomes, many of which are coastal. So you will likely find these little guys anywhere. What makes this mod so neat, though, is it also adds penguin armor, hats and weapons. These come into play with the 3 special penguins of this mod. The Flame Penguin, which only spawns in the Nether; the Ninja Penguin, which only spawns at night; and the Cloud Penguin, which only spawns in extreme biomes.

They each have special drops that allow you to create armor that gives you special abilities like underwater breathing, flame resistance, and speed. You can also create penguin hats in the likeness of each of the penguin species. And the penguin armor acts as camouflage so wild penguins will be more comfortable around you when you approach.

This mod adds four weapons. The Penguin Bow is slightly more durable and delivers more damage than the regular bow. The Flame Penguin Repeater adds more durability, velocity and damage than the Penguin Bow. And the Katana and Shuriken don’t deal too much damage but they are quite nifty. They can only be found by killing a ninja penguin.

The wiki has a lot of useful information for this mod as well.