Jack of all trades: temporarily boost any skill for a day as long as you never master any one skill.
Philosopher's Stone creation: After mastering some crafting skill, you intuitively know the recipe for a philosopher's stone, which can produce the elixir of life, and turn base metals to gold. You can only make one, and it's fueled by Sparks of Life. After producing so much elixir(which can prevent aging for a certain amount of time, preventing your spark of life from draining) or gold, you have to sacrifice one of your unused SoL's to fuel the stone. That way someone could be functionally immortal but still need Sparks.
Musical talent: for the best of bards. can play any instrument. NPC's will tip money if in earshot, and will be distracted (so you can play while someone else cuts their purses) can also be used to charm certain NPC's and animals. Maybe even have some method of having user-submitted songs available?
Blink: we all know what this does
Animal Possession: possess a horse to run fast, a bird to fly over walls, a rat to sneak into small places, a dog to track a scent. stuff like that. Maybe limit it to one type of animal per player.
Astral projection: your spirit can leave your body to see around you, go through walls, fly, etc. but you're body is defenseless while doing so. have friends with you.
painting?: more of a skill I guess. It'd be cool to roleplay a painter that travels the land to perfect their art. can craft paintings that are basically filtered screenshots of the game that can be framed and hanged on the wall.