Catalog the stars visible from your backyard.
Study with a shaman.
Read every book banned in your country.
Spend a month eating only food you grow.
Build a computer from scratch.
Handwrite your favorite book from cover to cover.
Follow a lover across continents.
Memorize a poem in its original language.
Learn a martial art that's practiced in only one small region.
Join Nautilus.
Don’t do it because your friend told you to. Do it because your friend told you not to.
What makes you special is the sum of your quests (see: specific knowledge).