A simple marriage of a compact storage technology and a nearly ubiquitous connector, USB flash drives long ago became heir to the floppy disk, a convenient way to move files between multiple computers.
Prices, which vary with capacity, buy you more capacity as time goes on.
According to NPD's Retail Tracking Service, the most popular capacity for a USB flash drive in 2010 was 4 gigabytes, which cost an average of $13. But low-capacity drives are so cheap that they are often given away as promotions.
But while the USB drive is simple and affordable, it has some limitations that are getting addressed by an array of products that bring creative spins on network and wireless capabilities to the familiar PC appendage.
Tazzle IT ($79.95) addresses a common issue of how difficult it can sometimes be to transfer information between a smartphone and a PC even when they are right next to each other, especially if you don't have a cable handy.
The slim half-height Bluetooth adapter makes it simple for you to view, transfer or print documents such as photos from a BlackBerry using a PC. Tazzle IT adds a couple of menu commands to BlackBerry applications that manage messages and photos.
Simply select what you want to send, and choose Tazzle IT from the application menu to send it to the PC using the adapter and running the software.
Once the PC and BlackBerry software is installed, Tazzle IT is easy to use, although you'll have to hunt among the BlackBerry's sometimes excessively long menus to find its features. Unfortunately, the product doesn't yet work with any other smartphones or with a Mac, and the speed of Bluetooth means that you may want to step up to a USB cable transfer for moving across lots of photos or long videos.
HSTI Wireless Media Stick
The chunky, plainly named and colored Wireless Media Stick ($119.99) 2.0 acts like most USB flash drives, but retains a live link back to the original PC or Mac -- or even multiple PCs and Macs -- in a home network.
If you copy a folder of photos to the Stick and attach it to, say, a digital picture frame, it can be updated every time you add photos to that folder without having to bring the stick back and load it up again.
You can even configure the Stick wirelessly with a Web browser to, for example, add access to shared network folders without having to physically insert the drive in the computers that are sharing them.
The Wireless Media Stick lives up to its promise but there are a few things to keep in mind. Since it has no storage itself, the PCs or Macs with the files on them will have to be on and connected to the network for it to work.
Also, some devices may not recognize new files added without restarting them or reinserting the Stick, and -- as with any USB drive -- the receiving device must be able to handle the format of the files on it.
Many USB-equipped Blu-ray players, for example, support only a few video file formats. In addition, using high-definition videos with the Stick may be challenging in some home networks. At times, high-definition movies streamed smoothly. At other times, they buffered and stuttered.
AirStash ($99.99) uses Wi-Fi to form a bridge with a destination device; it is the only of the four devices discussed herein that uses any local storage, but even that depends on the SD card used with it.
While it's not unusual to find smartphones and tablets with 16 or even 32 gigabytes of storage today, there's sometimes a need for more plentiful or more flexible storage.
The black and green AirStash looks somewhat like a double-wide USB memory card reader/writer, and can work as one. However, once you unplug it and press the power button, it acts as a miniature server to any Wi-Fi device that has a browser. You can access it via an iPad's Web browser and look at photos and even play videos using the iPad's larger screen.
Also, there's no need to involve the PC; AirStash can read SD cards directly from most digital cameras.
While AirStash will work with most modern smartphones, its user interface is designed to look like an iPhone app, and you'll get a few hours of use out of its necessarily small battery.
Also, just as with the Wireless Media Stick, you must make sure the client device can read the file format, and you may not have much luck streaming high-definition movies, but standard-definition moves should work fine.
Contrary to what its telltale vowel-starting name might imply, the iTwin ($99) won't duplicate an iPhone or iPad.
It doesn't even work with them (or even iMacs although Mac support is in the works). A two-headed USB stick available in gray or metallic green, the iTwin operates somewhat like the Wireless Media Stick; you copy a folder or even your whole hard disk, to the drive so it can be accessed from a remote device. However, there are a few differences.
On the plus side, unlike the Wireless Media Stick, which works only within a home network, the iTwin's live link back to the original PC can work across the Internet, so you can access your files from almost any place you have broadband access.
The company aptly describes the product as two ends of a cable without the cable.
However, there are some limitations. First, one half of the stick has to stay connected to the source PC, and iTwin can work with only one source PC at a time.
As with the Wireless Media Stick, that PC must stay on and connected to the home network. Unlike as with the Wireless Media Stick, though, iTwin can be used only with PCs as the destination.
And as with other products that provide a path back to you home PC through the Internet, access may be even slower than your broadband connection usually is. This is because iTwin depends on the data speed from your home up to the Internet, which is almost always slower than the speed down from the Internet.
Despite these limitations, the iTwin system is easy to understand and use, and worked well with firewalls that sometimes caused problems for other remote access products.