With all the NSA hooplah this past year, and mounting concerns over user security, it's not surprising that you might want to shield certain of your files from prying eyes. You can use any of a number of overly complicated solutions, including Terminal commands and expensive consultants, but software developer MacPaw wants to make it a bit easier for the average person with Hider 2 (Mac App Store link). Hider 2's normal price is $20, but MacPaw is currently offering the app for an introductory price of $10.
The app is a major update to the company's older MacHider, which let you hide files from public view by making them invisible. Hider 2 builds on that simple utility by adding a Mavericks-refined interface; a systemwide menu; AES-256 encryption for both files and folders; and support for notes, tags, and external drives.
When you first launch Hider, it asks you to supply a password for your vault; you can choose to store that password in your OS X Keychain. Once you create your vault, you see a window with the vault's contents (initially empty, of course). You get a single vault--you can't create separate vaults for, say, work and personal files.
Adding items to your vault--and, thus, hiding them--is a simple as drag and drop: Just find the files or folders you want to protect, drag them into the window, and Hider 2 immediately encrypts and hides those items from public view. Next to each item in your vault is a toggle to make that item visible again.
However, unlike many hiding programs, Hider 2 doesn't just make your files invisible to the average user. It actually copies those files to the app's own private, encrypted space on your drive and then deletes the items from their original locations. (If you have multiple drives, you can choose which one Hider 2 uses for its encrypted storage.) When you toggle an item's switch to Visible, Hider 2 copies the item back to its original location.
While Hider 2's approach is more secure than simply hiding files in place, it has a few important caveats to consider. First, Hider 2 doesn't securely delete files that you've moved to your vault--the original files are simply deleted as if you'd moved them to the Trash and emptied the Trash. This means that savvy malcontents could theoretically recover that data off your hard drive. This isn't something you'd likely need to worry about when it comes to your family members, but if you have data you need to keep absolutely secure, Hider 2 currently isn't your best encryption option. (MacPaw told Macworld that the company will be adding secure deletion in a future version.)
In addition, every time you hide or unhide a file or folder, that item must be copied and encrypted or decrypted, respectively, which can take time. With small files, the processing time is almost instantaneous, but larger folders (such as a 7GB folder I tested) take significantly longer.
Finally, this processing time wouldn't be as much of an issue if you could preview or edit files while they're in your vault--you wouldn't be swapping your files in and out very often. But you must remove an item from the vault to view or modify it. Similarly, while Hider supports Mavericks' Tags feature, you can't add or modify an item's tags while it's in your vault. (You can, however, create custom groups for your files while they're encrypted.)
Still, despite these nitpicks, Hider works remarkably smoothly. It's a great little tool for anyone looking for a digital hidey-hole, and the encryption is a nice bonus.