Apple laptops conspicuously lack HDMI ports for easy TV connectivity, but that doesn't mean they're not capable of outputting an HDMI signal; they just lack a dongle. A Mini DisplayPort-to-HDMI adapter will do the trick, and many don't cost more than $10. In fact, the Mini DisplayPort to HDMI Female Adapter Cable by Portta only costs $5.50. PC users and those with extra monitors might also consider investing in a Mini DisplayPort-to-VGA adapter, also readily available. We'd say this has a narrow use case, but anyone with an older VGA monitor could find it essential.
There's no built-in 3G on a MacBook...yet. You can still plug a 3G wireless card in via USB, though. These little sticks are getting ever cheaper and smaller, and while they'll ruin the clean look of the outside of your MacBook, they're essential for road warriors. Alternatively, consider a wireless hot spot. The pucklike devices stow away out of sight, offer fast Internet access, and can be used for multiple devices such as iPads or smartphones, too. (We love the Clear Spot 4G Apollo--just be sure to check the coverage map before buying it or any other cellular data product.)
Those who use the 13-inch MacBook Air, advance to the next slide. For all you 11-inch Air owners without an SD card slot, we sympathize. Believe us, we wish the 11-inch had an SD card slot, too. Unless you can do without, pony up $10 or so for a USB card reader and move on. Kingston and SanDisk make two good examples; there are many, many others.
A MacBook Air's 64GB, 128GB, or even 256GB--should you be able to afford it--isn't a lot of storage space compared with the 500GB of hard-drive space on an average mainstream laptop. A USB hard drive is a must, and prices have come down enough to make it a no-brainer purchase for local backups. A wireless NAS (network-attached storage) drive is an even better solution for home use: plug one in near your router, and no wires are required to access music, photos, and other data.
Admittedly, we rarely if ever use the DVD drive in our laptop anymore, but having one can be invaluable for disc-based software installation and burning backups of data. Apple makes its own DVD-RW SuperDrive for $79, but third-party alternatives are available for less.
The MacBook Air lacks an Ethernet jack, which means that it's Wi-Fi or bust unless you have an adapter. For true road warriors, a hard-line connection is a must--and some hotel rooms offer free Ethernet but charge you for Wi-Fi. Apple makes its own USB Ethernet Adapter, but there are also cheaper alternatives.
Amazon, iCloud, Dropbox, or even Google Docs/Music/Picasa. Whatever you choose, we'd recommend having at least one good method for online cloud storage, especially since onboard storage space on the Air is limited. Amazon, Google, and Apple offer compelling cloud music services that provide alternatives to filling a hard drive, while services like Dropbox are useful for quickly storing and accessing files.
There are dozens of cases and sleeves available for the MacBook Air, ranging from the ridiculous to the sublime. It doesn't matter what you get--we just recommend you get one, period. The Air is too sleek and pretty to get scratched up in a bag. Check out our MacBook Air case and sleeve roundup to window-shop.
It's easy to run Windows on a Mac, and you don't even need Apple's Boot Camp to do it. Parallels will run Windows from within OS X, eliminating the need for rebooting. It's the fastest way to turn a MacBook Air into a Windows Ultrabook. Other alternatives: using Boot Camp and installing Windows 7.
The $999 price is a lot to pay for a monitor, but Apple's upcoming Thunderbolt Display is possibly the ultimate MacBook Air peripheral. The 27-inch display connects via Thunderbolt and not only conveys audio and video, but also has three USB 2.0 ports, a FireWire 800 port, and a Gigabit Ethernet port, all of which send their data back to the MacBook Air via that one Thunderbolt cable. An HD Webcam in the monitor will work with FaceTime videoconferencing, too. You could also just get a cheaper monitor and use Mini DisplayPort or HDMI converter cables, but for an all-in-one dock solution it's hard to beat this executive combo.