I’ve been pondering the route “Quarterlife” has taken to network television. The series (which ABC rejected) became a Web-only series, where it grew so popular that NBC has picked it up as a midseason replacement.

While many have touted “Quarterlife” as a first, it’s worth remembering that “South Park” got its start as a short film the show’s creators developed for a Fox executive to use as an emailed video Christmas card.

Since online shows have grabbed the attention of network executives as a new source of material, I’m wondering if it can work in reverse. Think about cancelled shows that have dedicated—even rabid—fans. They undertake petition drives and other efforts to save their favorite shows, but you can count on one hand the number of times these efforts have succeeded. (I’m thinking “Cagney & Lacey” and “Jericho,” but can’t think of any others.)

But if the fan base is large enough, why not take the series to the Web? Take Firefly, for example. Fox didn’t give Joss Whedon’s sci-fi/cowboy show a chance to build an audience. Early fans loved it, but most of us who came to appreciate the show did so after watching the DVD. So why couldn’t Whedon continue producing the show funded by online advertising and donations from fans? Firefly fans probably would have been happy to pay $10 for access to a new season’s worth of shows. If there are 50,000 fans, that’s $500,000—only about half of what it cost to produce a single episode, but as new fans come on board—supplemented by advertising—it could support the development of enough episodes to ignite new fan enthusiasm and lead another network to pick it up.

It’ll be interesting to see if any popular-but-cancelled shows try this approach.