Since people already listing the popular ones, I'mma say Byakugan which is surprisingly underrated.
It's one of the most useful ability in hand to hand combat.
In real life, if I were to engage in a war, snipers can't hit me. And I can see from kilometres away so it would be useful for spying and infiltration mission. X-Ray vision, Infrared, can see people's chakra, etc. in general are very handy.
In daily life though, I can just challenge my friends to a staring contest and I would automatically win because Byakugan can go for a long period of time without blinking.
Of course if I were to transport to Naruto world, like I said above with the war scenario, Byakugan is useful for stealth missions.