FATAL_SE7EN  This is ridiculous how could the developer charge money for this... all this does is simply execute a basic UNIX system function, it puts a period in front of a file so that the system treats it as a system file and so renders in invisible. But anyone with RUDIMENTARY UNIX knowledge would know how to sidestep this "Security Measure". The fact that the developer charges for this makes me angry... I bet I could write an applescript that does this exact function in less than 20 MINUTES. I pity the fool that "secures" Bank details and credit card numbers with this.. People these days.. "Sigh"  
(Version '08b87)

IANWEIR  Security through stupidity - anybody who thinks that this will make their files secure, and safe from prying eyes deserves to be ripped off for the $19.95 this sorry excuse for a program costs  
(Version 4.0b)

ZZAMBONI  I cannot believe anyone would pay for this. It borders on the unethical to charge for this software, which offers no protection at all. All it does is rename the file to be protected to start with a period, which in Unix means it will not be shown in normal directory listings, but offers NO protection whatsoever. Try this: make a file on your desktop "invisible" using this software. Now open the Terminal, and type the following commands:

cd Desktop;

ls -a

Scroll up (if necessary), and you will see your file there, with the original name preceded by a dot. You can type "open .filename" (replacing filename as appropriate) to open the file.

If you want to have more protection, set the permissons on the file so only you can access it (open the file's Info dialog, and look at the "Ownership and permissions" tab). That at least will really prevent other users from accessing it. If you want to have even more protection, encrypt it using File Vault, which also comes with MacOS X.  
(Version 3.6)

ANONYMOUS  way to expensive! There are others with more options for less money.

Plus it crashed quite often!  
(Version 3.1)

ANONYMOUS  P. T. Barnum was right. One born every minute. (Make that second with today's birth rates.)

If you want to keep people out of your stuff without going to the trouble of creating a faux user account (who wants to log out/in just to see document files?), password encrypt the folder with DiskCopy (part of the system installation), PGP, StuffIt, et al. Tons of encryption apps for OS X out there that are very secure.

And if you really need it to be invisible, make it invisible with any number of truly useful utilities like File Buddy that do so much more.

With the Go To Folder command, nothing is invisible. Same with Sherlock, just select invisible/on and a drive and you see all invisible files and folders. Same with dev apps like Resorcerer and plenty of others. Invisible is only protection against the computer illiterate and those who just aren't looking.  
(Version 2.6.4)

MACMAN  Even better, use file vault and a separate user account with a strong password. The NSA could get in, but probably not anyone else....  
(Version 2.6.4)

CAREFUL MAC USER  Wheww... wife wont be able to see my stash of pic and videos  
(Version 2.6.2)

ANONYMOUS  Rename your folder from foldername to .foldername - that is for what you can pay 15$ or more?

The price is not fair! This price says: hey, are you a really stupid user?  
(Version 2.6)

ANONYMOUS  Please make sure your application has a reason to exist on OSX before porting it to OSX. Thank you.  
(Version 2.6)

ANONYMOUS  Secret Folder ROCKS!!!!. If you have stuff to hide and you don't want anyone to find even a way to trace its existence, use Secret folder.  
(Version 2.4.3)