Deku Nut

Deku Nuts are items from Ocarina of Time, Majora's Mask and Twilight Princess. Deku Nuts are the dried buds of Deku Babas as opposed to Deku Sticks which are the stalks. Deku Nuts are odd in that they erupt into a blinding flash on impact with a surface. They were famously used by the Sheikah to quickly leave an area unseen--one would literally vanish after throwing one. However most of the time, the only effect of a thrown Deku Nut is that it stuns anything around the flash giving them a fading blue hue until the paralyzing effect wears off. Oddly enough, powerful figures such as Ganon may be injured by Deku Nuts along with very weak creatures such as Shabom.

Deku Nuts are the weapon of choice of Deku Scrubs, which spit them from their mouths. Surprisingly, the nuts utilized by Scrubs do not explode on impact, and instead simply deal damage and crumble; however, that being said, Deku Link is able to drop Deku Nuts while flying using a Deku Flower which have the same effect throwing nuts. Besides being used for battle, Deku Nuts also hold aesthetic value for the Deku Royalty in particular, as the Deku King's scepter is adorned with a large Deku Nut on top.

Deku Nuts in Twilight Princess cannot be used as items, but can be picked up from deceased Deku Babas and thrown like jars or rocks. They will not explode or produce a flash, but instead Deku Seeds inside which can be used in the Slingshot.

Deku Nuts are also used as items in Super Smash Bros. Brawl. When thrown at a nearby enemy, they are stunned.

Trivia
The Great Deku Tree's seeds in The Wind Waker look like giant Deku Nuts.