By Robert Isenberg
Special to MSN Entertainment

What is it about people getting trapped on remote islands? Why do we love to watch TV shows about tattered nomads stuck in the middle of nowhere, building basic tools out of coconuts and bamboo? And it's not just unmapped tropical cays: There's also outer space, underground and, for some unlucky aliens, Earth itself.

As "Lost" ended its fourth season, we finally got to see how several of Oceanic 815's survivors actually made it off the island. Which made us wonder, who are the castaways of TV's past, and how did they journey back from the frontier? If there's one thing that's certain, most shows get axed before there's even hope of rescue, but the point is, they tried -- and entertained us along the way. Here's a glance at some favorite marooned casts:

"Gilligan's Island" (1964-67)
There's hardly a red-blooded American who can't hum the "Gilligan's Island" theme song, name the characters or recall what cereal he or she was eating while watching the reruns. For three years Americans tuned in to this favorite screwball comedy, heeding the Professor's brilliant plans for escape, and then laughing at Gilligan's plan-foiling klutziness. But life improved for the Gilligan group: First, the once black-and-white island discovered Technicolor in episode 37. Then the show's tired formula of good-ideas-gone-bad found new life when Gilligan started having vivid dreams of vampires, werewolves and Sherlock Holmes. If only he could have dreamed up a spin-off; CBS abruptly cancelled the show in 1967, reducing Gilligan's island to a quick stop on the bus tour of Universal Studios.

"Hard Time on Planet Earth" (1989)
Sure, the beefy lead was named "Jesse," and his sidekick was a badly animated floating eye named "Control," but this one-season sci-fi comedy was a fun little satire about an extraterrestrial war criminal who gets sentenced to hard time -- on our very own planet. Confused by everything from cash money to ball-point pens (admit it, it's an oxymoron), Jesse and Control were the perfect odd couple from outer space. The CBS series was quickly cancelled, but Jesse joins a host of other forever-stranded TV aliens: Mork, ALF, and even slime-spewing Roger from "American Dad."

"Lost in Space" (1965-68)
This classic sci-fi, action-adventure hoke-fest continued the tradition of stranded Robinsons (Robinson Crusoe, Swiss Family Robinson), though the Robinsons of "Lost in Space" were the first to own a truly obnoxious silver robot shaped like a blinking trashcan. For every planet they discovered, we could expect the Robinsons to face super-human trouble and the robot's nasally wail, "Danger, Will Robinson! Danger!" (Why did they build a robot that only sensed danger? Why not a robot with, say, a rocket launcher built into it?). The show's name said it all (lost, space, not too complicated), but sadly, this intergalactic nuclear family would remain lost: The series was abruptly cancelled by CBS. But we can be confident that the Robinsons never made it home, as the show takes place in the far-future date of 1997 (the year after "Star Trek" claimed Khan would take over the Earth with an army of super-men).

"Land of the Lost" (1974-77)
Rafting through the wilderness has its own inherent dangers, but if you go rafting with Rick, Will and Holly, you might tumble over a waterfall and end up battling a giant Tyrannosaurus Rex named "Grumpy." What's astounding about this primal fantasy isn't the hairy makeup on the "Paku" cavemen, or that the tormented trio never reached home. Rather, it's that NBC dedicated 43 episodes to "Land of the Lost" -- and they're all available on DVD!

"Quantum Leap" (1989-93)
Perhaps the most awkward of them all -- if only because of how many times Scott Bakula had to wear a dress -- "Quantum Leap" took an innovative spin on the "lost" protagonist: Nice guy Sam is struck traveling through time, inhabiting people's bodies just long enough to solve their personal problems -- a combination of role-playing therapy and "Invasion of the Body Snatchers." Critically acclaimed and widely beloved, "Quantum Leap" actually earned a true finale, when Sam finds his own body, but long before he met his wife and fathered his daughter -- a real shocker for the series' fans.

"Survivor" (2000-present)
In its half-decade of sweaty, soul-crushing malevolence, "Survivor" has taught us one thing: People are mean. Spanning two hemispheres and six rain-forested islands, "Survivor" has revealed time and again just what self-absorbed hotties will do to win a cool mil and a Pontiac Aztek. Gritty, cutthroat and unpleasantly democratic, "Survivor" boasts the winning combination of "Clueless" and "Lord of the Flies" -- and it continues to be our candidate for Reality Show Most Likely to Cause Physical Harm to Its Own Contestants. CBS wouldn't cancel this show if its ratings depended on it, and as the blazing sun of Exile Island continues to punish our not-yet-voted-off competitors, we'll once again sense the true meaning of "natural selection." On the plus side, you know that the "Survivor" survivors -- whether they won or lost -- get to come home with a nice tan, and they're almost guaranteed an interview with David Letterman. Tough luck for the Robinsons.

Robert Isenberg is a freelance writer, stage actor, comedian and playwright. Raised in Vermont, he discovered television -- as well as gas heat, electric stoves, e-mail and baklava -- when he moved to Pittsburgh, where he lives and performs.