User can sense the presence of energy, whether they are electromagnetic (magnetic/infrared), psionic, magical, spiritual, etc. and possibly gain detailed understanding about the energy they are sensing, including the amount/size of energy they are sensing and whether it is hidden.
Bridge Carson/S.P.D. Green Ranger (Power Ranger S.P.D.)
Linda Tavara (Heroes)
Margaret Isobel Thoreaux (Smallville)
Adamai (Wakfu); via Wakfu Sensing
Grougaloragran (Wakfu); via Wakfu Sensing
Yugo (Wakfu); via Wakfu Sensing
Leena (Warehouse 13)
Users of Kenbunshoku/Observation Haki (One Piece)
Drusilla (Buffy the Vampire Slayer)
Users of Eagle Vision/Eagle Sense (Assassin's Creed)
Z-Fighters (Dragon Ball); via Ki Sense
Sir Aaron (Pokemon: Lucario and the Mystery of Mew)
Meisters (Soul Eater)
Users of Pesquisa (Bleach)
Sensor type ninja (Naruto)
Senjutsu users (Naruto)
Ivy Walker (The Village)
Neo (The Matrix)
Others (Night Watch)
Nikodemos (Thieves' World)
Luna (Incarnations of Immortality)
Geordi La Forge (Star Trek: The Next Generation)
Rui (Pokemon Colosseum)
Wolf Link (The Legend of Zelda: Twilight Princess)
Xenomorphs (Aliens vs. Predator)
Nick Scryer (Psi-Ops: The Mindgate Conspiracy)
Miraluka (Star Wars)
Alex Mercer (Prototype)
Cole MacGrath (Infamous); via Radar Pulse
Alex Mercer (Prototype)
Shalimar Fox (Mutant X)
Predators (Aliens vs. Predator)
Gekkos (Metal Gear Solid 4: Guns of the Patriots)
Aleera (Van Helsing)
Gyokuro Shuzen (Rosario + Vampire); via Enemy Zero
Mr. Hyde (The League of Extraordinary Gentlemen)
Maya (Redakai: Conquer the Kairu)
Samus Aran (Metroid Prime)
Boros (One Punch Man)
Gwen Tennyson (Ben 10)
Charmcaster (Ben 10: Ailen Force)
Son Goku (Dragon Ball) senses King Piccolo's ki.
The Z-fighters (Dragon Ball Z) sense Future Trunks's Super Saiyan ki.
As a sensor-type shinobi, Ino Yamanaka (Naruto) can detect the presence of other people by directly sensing their chakra.
Karin (Naruto) can use her unique sensory ability, the Mind's Eye of the Kagura, to track any targets through their chakra signature.
Gyokuro Shuzen (Rosario + Vampire) using Enemy Zero...
...to sense and track any and all monster energy within a several thousand mile radius.
Kenbunshoku/Observation Haki users like Monkey D. Luffy (One Piece) can detect the "intent" of any living creature.
Knuckles the Echidna (Sonic the Hedgehog), can sense the chaos energy of the Chaos Emeralds, the Master Emerald, and similar objects like Sol Emeralds, and can track down their "signals", making him a living Emerald Detector.