Video is a huge part of portable computing these days. Whether it's viewing YouTube clips, streaming movies from Netflix, catching up on a missed show via Hulu, or enjoying a DVD on a long flight, everyone loves to watch. Laptops can obviously do it all, but video capabilities are a common selling point of the modern smartphone, too.
Laptop: A laptop offers the best video viewing, hands down. A full-fledged laptop probably has an optical drive that you can use to watch DVDs (or even Blu-ray movies, if it's the appropriate drive). The large, high-res screens are easy to look at for extended periods, and good speakers are an option that you won't find with the other two types of devices. Nobody wants to huddle around a 9-inch screen, let alone a 3.5-inch display, to share a laugh at a video of some crazy kids almost hurting themselves on YouTube.
Netbook: You get better battery life with a netbook, but you give up too much in the process. The machine doesn't have an optical drive, so DVDs or Blu-ray movies are out. The 9- to 11-inch screens are hard to watch for extended periods, and even harder to share with friends--and good luck finding a netbook with decent speakers. Sure, all of the online video services are still at your disposal with a netbook, but you'd be much happier watching them on a bigger laptop.
Smartphone: Smartphones are really useful only for very short video clips from a limited number of providers. No smartphone has legitimate Hulu access. Netflix streaming may be coming to smartphones, but it's not there quite yet. Many sites that rely on Flash won't stream video on smartphones until Android 2.2 comes. Even when you can find something to watch, staring at a screen smaller than 4 inches gets old in a hurry.
What to buy: Laptops take the crown. You can watch whatever you want, whenever you want, on a screen big enough and with speakers good enough to actually enjoy it. The only real drawback is battery life: Shop carefully for a laptop that will get you through a whole movie or two, especially if watching on a plane or during a long road trip is a priority.
Need to kill a little free time? Get your game on. Portable gaming is huge, but you'll find major differences in the quality and quantity of games available for these three portable devices. Whether you're a casual player or a serious gamer, you have important choices to make regarding your portable game machine.
Laptop: A decent laptop for gaming has a dedicated graphics chip, and thus costs a little more than basic entry-level models, but you can still get one cheaply enough. If you shop carefully, a good game-capable laptop shouldn't cost you more than $1000. With such a machine, you have access to the huge library of Windows games and great gaming services like Steam, plus Web-based games, user mods, and more. You have to shop carefully to find a laptop that plays games really well, and you'll likely end up with a model that's a little bigger and heavier--with less battery life--than a laptop that isn't appropriate for games. Many PC games don't play well with a touchpad, so you'll also need a mouse and an appropriate surface to play on; you lose some portability as a result.
Netbook: Just say no. From underpowered CPUs to anemic graphics capabilities to low amounts of RAM to cramped screens, netbooks make terrible gaming computers. You can get away with simple in-browser games and some years-old classics, but you won't have a good time with modern games at all.
Smartphone: Photographers often say that the best camera is the one you have with you, and the same could be said of game machines. When you have some time to kill, a fancy gaming laptop does you no good if you don't have it with you, but your phone almost never leaves your side. A phone is small enough to use easily on a bus or train, and since most phone games are designed to be played in short sessions, you can get 5 minutes in, quit, and play more later.
Among smartphones, the iPhone has by far the biggest and best games library, easily rivaling the libraries of dedicated handheld game systems. Android phones come in a distant second, but the gaming selection and quality on the Android Market is growing quickly. Blackberry devices aren't exactly game-free, but have the worst selection of all. Microsoft's upcoming Windows Phone 7 may be the smartphone gaming option to beat, considering its integration of Xbox Live and partnerships with major game publishers.
What to buy: If the games you like are big, full-featured, triple-A titles that have high production values and take hours to play, you want a laptop with a discrete graphics chip. Avoid netbooks and laptops with integrated graphics, unless you care only about playing simple browser-based games. For gaming on the go, it's hard to beat the iPhone, though Android phones are coming on strong. After all, what's a better portable game machine than the one you already carry around every day?