Have you ever wanted to ditch your clunky laptop? Perhaps you were meeting a client for dinner or friends at a bar after work. Or you were trying to catch a flight in the morning and had to fumble with your laptop at the airport security check.Sure, laptops have become lighter, thinner and less cumbersome (think: MacBook Air, Dell Adamo and netbooks). But a laptop still needs to be carried around town in a backpack or other carrying case (or so that's what IT says). And this means checking it at coat-checks, making sure you don't forget it inside taxi cabs, and keeping a constant eye out for laptop thieves.[ Laptops don't feel the love, reports CIO. | Reviewers weigh in on iPhone 3.0. ]But help is on the way: As smartphones grow in functionality (the iPhone 3G S and iPhone 3.0), you might be able to forego the laptop in favor of a smartphone. Imagine the freedom that comes with a computer on your hip, not strapped to your back.Before we get carried away, though, it should be noted that a smartphone can't replace a computer\u2014at least, not yet. "Smartphones are still content consumption devices, not content creation ones," says Gartner analyst Ken Dulaney. "Every knowledge worker has to do content creation, so you've got to have a desktop or a laptop to do it."Today, a smartphone might be able to replace a laptop when you're on the road and then sync to a desktop at the home or office where you'll do most of your content creation. "That's a very valid scenario in some cases," Dulaney says.In the past, mobile laptops replaced desktops even though desktops were cheaper and more powerful. Now desktops\u2014thanks to smartphones\u2014have an opportunity to turn the tables on laptops.How to Make the Scenario WorkThat's what Don MacRae, a former investment bank executive and avid laptop user, hopes to do. He's making the leap: dumping his old laptop, buying a cheap PC and hoping his BlackBerry 8330 will handle all his computing needs when he's on the road.One of the reasons for the decision, MacRae says, is that his BlackBerry now runs "critical" apps comparable to those on his laptop. His critical BlackBerry apps include: Opera Mini, reQuall, Documents to Go, Yahoo Go, Viigo, among others. He's also getting a Bluetooth portable keyboard to keep in his suitcase for content-creation emergencies."If you're going to be crunching numbers on an Excel spreadsheet or writing documents all day long, you're not going to want to do that on a BlackBerry," MacRae says. "But if you're managing people and on the phone a lot, or in sales and going on a quick overnighter to see a client, you could make a good case for traveling light with just a BlackBerry."It's still early in MacRae's big experiment, but he can already see problem areas. For instance, MacRae worries that he might one day need a document or e-mail from the archives that aren't on his BlackBerry but on his computer back home. Or he might be unable to modify an important attachment.Compatibility Is Where You Run AfoulDulaney says that MacRae's worries are the tip of the iceberg. Gartner recommends companies don't go this route, in part because users may run afoul of IT policies and face compatibility and performance issues.As to IT policy, Gartner tells companies to require users to view all company e-mails and attachments on a PC or laptop. That's because smartphones might not convert attachments properly. Even Documents to Go doesn't run all the macros, Dulaney says, and thus you might not be able to see the document fully.With performance, just try giving presentations on a BlackBerry. "Performance is going to be slow," Dulaney says, "and you won't be able to run all the software." Hiccups in a sales presentation, of course, can be deal killers.The biggest problem, though, concerns compatibility. Consider iPhone OS, which runs a shrunken version of OS X. There are some layers of OS X that simply don't run on the iPhone. "Compatibility is always a problem because of the nature of running different operating systems with different utilities on different platforms," Dulaney says.Data in slideshows, Excel spreadsheets and Word documents might be viewable on a smartphone, but the additional extensions and functionality may not be there. Even the viewing of Windows Office content can be tricky because Windows Office wasn't built to be scaled down and viewed on a small smartphone screen."Sure you could hook up a keyboard, power supply and larger screen to an iPhone and run Office\u2014in theory, at least\u2014but have you gained anything?" Dulaney asks. "You'd probably be better off with a laptop or netbook."But Dulaney does say that the smartphone-desktop combo can work in some cases, particularly for European business folks who do a lot of day trips and have access to Internet kiosks. Here in the U.S., though, business folks tend to do more overnight trips."The more you stay away from your desk," Dulaney says, "the more difficulty you're going to have."Got a different take? Send me an email at email@example.com. Or follow me on Twitter @kaneshige. Follow everything from CIO.com on Twitter @CIOonline.