17. The Twilight Zone (1959-1964)

Anyone who's ever suffered a hangover on New Year's Day has probably entered The Twilight Zone on their couch during the annual marathon. This groundbreaking sci-fi anthology show has served as inspiration for countless films and TV shows. There would likely be no Twin Peaks or Lost without The Twilight Zone. (Photo: Corbis)

16. The X-Files (1993-2002)

The truth is out there, and it's widely in favor of The X-Files. This multi-award-winning show, featuring a skeptic FBI agent and a true-believer partner, made more than a few watchers pay closer attention to unidentified flying objects. (Photo: Corbis)

15. Sliders (1995-2000)

This time-traveling adventure about a boy genius who accidentally creates a portal to a parallel universe is an instant geek classic. If that previous sentence wasn't proof enough for you, the show features a humanoid species called The Kromaggs. Oh: And it was so loved by fans that after Fox cancelled the show, it was saved by the Sci-Fi Channel for its last two seasons. (Photo: Universal Television)

14. Quantum Leap (1989-1993)

Scientist Sam Beckett jumps the gun on one of his experiments and ends up trapped through time, constantly forced to experience others' lives instead of his own. The hokey sci-fi show is full of campy characters like Rappin' Al, Dr. Ruth, a vampire, and…Elvis. (Photo: Universal Television)

13. Star Trek: Deep Space Nine (1993-1999)

This Star Trek series had a lasting impact on genre television. The grittiest TV installation in the franchise, Deep Space Nine paved the way for things we take for granted on science fiction and fantasy television now. Its religious themes, mismatched romantic pairings, and longstanding story arcs are only a few reasons why it continues to gather new audience members to this day. Metacritic gives it a 74, and an 8.2 user average. (Photo: Corbis)

12. Star Trek: Voyager (1995-2001)

Beam me up, Janeway! One of the highest-rated Star Trek shows on Metacritic, Voyager has plenty of reasons to geek out over, like its super cool female commander, the holographic medical care, and all of those old-school Trekker references for vintage Vulcan fans. (Photo: Corbis)

11. Firefly (2002-2003)

If the wild west ever happened in space, you'd have a world like Firefly. This sci-fi favorite has a 9.2 user rating on Metacritic, and the show was so popular with its fans it even got a movie spin-off (Serenity). Sadly, it was short-lived, but the brainchild of Joss Whedon gained numerous loyal fans who still cosplay its characters, such as the enigmatic Captain Mal and the drop-dead gorgeous Inara Serra. (Photo: Corbis)

10. Battlestar Galactica (2004-2009)

Also boasting an impressive 9.2 user rating on Metacritic, the second Battlestar saga follows a starship of sole survivors after most of their planet has been taken over by sentient robots called Cylons. It doesn't get much better for geeks than Dr. Baltar, a computer systems engineer who has a 6-foot-tall blond model (and robot) girlfriend. Galactica was also name-checked by the Dilbert comic strip, an uber geek credential. (Photo: Corbis)

9. Doctor Who (1963-1989)

The classic Doctor Who still has an intense geek following, which especially becomes obvious during Comic-Con. William Hartnell, the very first actor to ever play the time-traveling Doctor, had a distinctive costume and personality traits that have been lovingly recreated by generations of fans. The costume also set a precedent for each Doctor to follow. The crazy striped scarves, the puffy hairdos, and the flashy bow-ties all became unforgettable looks. (Photo: Corbis)

8. The Walking Dead (2010-2015)

Zombies that go boo and eat your brains in the night: We've seen it before. But for some reason, when you make a TV show about the humans who are left behind and struggling to stay alive, it becomes a colossal hit. Well received by both critics and audiences, The Walking Dead is unrelenting, riveting, action-packed television, and for those of you who love to geek out on zombies, but still want a good story, this show's for you. The show was co-created by writer Robert Kirkman, who began writing the comics back in 2003. (Photo: Corbis)

7. Lost (2004-2010)

Sure it's easy to get lost in Lost, and the mess of a conclusion infuriated fans, but the polar bears, smoke monsters, moving islands, crazy conspiracy theories, and Penny's boat kept the show afloat for six seasons. With a Metacritic score of 86, and 9.1 user average, Lost received not only awards, but also an enduring following. (Photo: Corbis)

6. Doctor Who (2005-2015)

The smart and quirky Doctor returned after a 10-year hiatus with actor Christopher Eccleston. He starred on the show for a year until fan favorite David Tennant came into our lives. There are plenty of reasons why Doctor Who is one of the geekiest shows ever, including, but not limited to, The Daleks (exterminate!), The Doctor's sonic screwdriver, and of course, Matt Smith's very British bow tie. (Photo: Flickr Commons: bainespal)

5. Buffy the Vampire Slayer (1997-2003)

Another one of Joss Whedon's babies, Buffy became an instant teen favorite. When you have to survive both high school and monsters simultaneously, you deserve to have your own TV show. Plus, Buffy's costars Angel, Xander, Willow, and Spike all had us coming back for more slaying…and homecoming dances. Metacritic gives it an 80, with an audience score of 9.0. (Photo: Corbis)

4. Sherlock (2010-2015)

Elementary it is not, my Dear Watson! With a steady 85 Metascore and a 9.1 user rating, the modern take on Mr. Holmes has become a global geek sensation, due to the undeniable chemistry of its leading men, Benedict Cumberbatch, and Martin Freeman, as well as some wicked-clever story lines and homages to the original Conan Doyle stories. (Photo: Corbis)

3. Star Trek: The Next Generation

Its creation was fraught with power struggles. Its sentient robot character was hokey and overacted. Its conflicts were clunky. But this show's legacy is undeniable: Despite its many flaws, this late-1980s TV staple re-awakened the Star Trek franchise so effectively that, to this day, it's stronger than ever. (Photo: Corbis)

2. Twin Peaks (1990-1991)

Who killed Laura Palmer? Even with a straight answer, you may be confused by all the weirdness in this show, but that's part of its geeky beauty. The two-season cult hit of the early 1990s, about a sleepy, creepy town, brought dark and quirky film director David Lynch to TV. The series clocks in at 96 on Metacritic, with a user average of 9.3. (Photo: Lynch/Frost Productions)

1. Star Trek: The Original Series

No TV series fired more imaginations, electrified more young rocketeers, or inspired more geeks than this grand-daddy of all sci-fi series. Even its cast was groundbreaking; a kiss between Captain Kirk and Lt. Uhura was the first interracial lip-lock on American TV. (Photo: Corbis)