Amazon Prime Day is in its final hours, but you can still save a ton of cash on essentials—like external drives, a necessary accessory for all your backups. (You are backing up your files, right?) If you have a lot of data to store, you’re in luck, because the price on a Western Digital Elements 16TB external hard drive is down to $228, or 26 percent off. After monitoring prices for the last year, I like this particular deal for how low the price is, as this popular, spacious drive has been much more expensive since last fall. This USB 3.0 desktop hard drive is meant for holding massive collec…