By Lou Carlozo, dealnews contributor We just recently wrote about some super sleuthy spy gadgets, and again are here to remind you that no good spy would be caught red-handed with paper documents. Instead, clever little portable storage devices are essential tools for everyday spies, and well, folks who are not spies. We're sure you, too, can make good use of these flash drives, memory cards, and an external hard drive. Fantom Diamond 2TB USB 2.0 External Hard Drive Vendor: Buy.com Price: $99.99 via $25 mail-in rebate with free shipping Lowest By: $47 Expires: March 18 Is It Worth It?: Let's put this in perspective: two TB of data storage is enough to hold all the songs ever recorded by the Beatles, Led Zeppelin, and Lady Gaga — with plenty of room to spare for the blueprints to all your secret spy lairs all over the world your thesis dissertation, of course. With a $25 mail-in rebate you'll only be paying $100, or a whopping $0.05/GB for this drive, which features a 32MB cache. But hurry, this rebate will self-destruct on March 18. Kingston 16GB DataTraveler 108 USB 2.0 Flash Drive Vendor: Buy.com Price: $12.95 with free shipping Lowest By: $2 Is It Worth It?: This handy flash drive has a swivel cover that makes it look like a futuristic data storage device, which of course it is (especially compared to floppy disks — yes, with a k!) The data storage on this device will run you just $0.81/GB, and these drives are ideal for storing everything from Word documents to theme music. More importantly, this reliable brand-name drive is an Editors' Choice deal. Lexar 128GB Echo MX USB 2.0 Flash Drive Vendor: Adorama Price: $99.95 with free shipping Lowest By: $8 Is It Worth It?: This Lexar drive not only features a capacity meter for measuring the amount of storage available, it offers eight times the space of the above-listed Kingston flash drive. It's an Editors' Choice deal, and its memory costs just $0.78/GB — the lowest price for a 128GB drive we've ever seen. Lexar 32GB microSDHC Memory Card bundled with a Lexar Card Reader Vendor: Amazon Price: $37.88 with free shipping Lowest By: $4 Is It Worth It?: This Lexar 32GB memory card has enough storage space for a number of backup files with room to spare. And to make the most use of your storage (which breaks down to a mere $1.18/GB), this high capacity card comes bundled with a handy card reader. Kingston 16GB microSDHC Memory Card Vendor: Target Price: $14.99 with free shipping Lowest by: $10 Is It Worth It?: If you're more inclined to buy only what you need in terms of storage space, pick up this 16GB memory card for just $0.94/GB. While this is the least expensive 16GB Class 10 microSDHC card we've seen without rebate hassles, you'll have to wait about two weeks for shipment, as this item is currently backordered. Front page photo credit: Mobile Office Lou Carlozo is a dealnews contributing writer. He covers personal finance for Reuters Wealth, and was most recently the managing editor of WalletPop.com, and before that a veteran columnist at the Chicago Tribune. Follow @dealnewsfeature on Twitter for the latest roundups, price trend info, and stories. You can also sign up for an email alert for all dealnews features.