Spriggan Sap

Weight	Base Value
0.2	5

Alchemical Effects
Damage Magicka Regen 100% for 5 sec	Fortify Enchanting 1% for 30 sec

00063B5F

Locations

One in Arcadia's Cauldron on the counter. (Respawns)
Two in the alchemy room (2nd floor) of the Hall of Countenance at the College of Winterhold. (Respawns). Also, at the left side of the Arch-Mage's Quarters, on the shelves.
Sold by the various alchemy vendors.
Honeyside (The house available in Riften) – the bottom shelf to the left of the Alchemy Table in the basement. (Doesn't respawn)
Proudspire Manor (The house available in Solitude) when you purchase the Alchemy Room. 2 are on the bottom shelf by the table itself. There is also one in the bottom box to the left of the Alchemy Table. (Doesn't respawn)
One on the shelf of the Alchemy and Enchanting area in Fort Dawnguard with the Dawnguard Plug-in. (Respawns)
One on the bottom row of the shelves next to the Alchemy Lab in Mistveil Keep in Riften. (Respawns)
One in The Mortar and Pestle in Dawnstar. (Respawns)
Behind the counter in Grave Concoctions in Falkreath.

Main article: Potions (Skyrim)

Damage Magicka Regen	Fortify Enchanting	Fortify Smithing	Fortify Alteration
Ancestor Moth Wing ^DG Bear Claws Blue Butterfly Wing † Blue Mountain Flower Burnt Spriggan Wood ^DR† Chaurus Hunter Antennae ^DG Chicken's Egg Glow Dust Hanging Moss Hawk's Egg ^HF Human Heart Jarrin Root Nightshade Spider Egg	Ancestor Moth Wing ^DG Blue Butterfly Wing † Chaurus Hunter Antennae ^DG Hagraven Claw Snowberries Spawn Ash ^DR	Blisterwort Glowing Mushroom Sabre Cat Tooth	Burnt Spriggan Wood ^DR† Grass Pod River Betty

† multiple effects

Contrary to popular belief, this item cannot be looted from Spriggans, only their Taproot can. The only way to acquire it is from Merchants selling Alchemy supplies.
Spriggan Sap's properties seem to be focused on improving crafting abilities, as it improves Smithing and Enchanting.