John's Little Script - John Delavera orignally sold this excellent script for protecting content.  He's not longer offering it, but some of his resellers are, and it's a great deal for $47.00. Completely lock someone out of any area of your website, requiring a username/password and integrates automatically with PayPal, ClickBank and 2Checkout.  Help videos included too.

DLGuard - One of the better membership software management scripts available. Supports all major payment processors (over 15 at the present time).

DAP - Digital Access Pass - A great protection software script. It can protect a standard website (folder or directory) or it can work within WordPress as a plugin to lock down an entire blog. Built in autoresponder and affiliate system, upselling, and online store system and forum integration is also available.

Sitelok- excellent site protection software which also has options to setup a membership website. Up to 50 custom profile fields can be defined and a integration plugin for PayPal is available.

Omnisecure - An all in one solution that covers membership management, coupons, affiliate program and email autoresponder with SMTP capabilities. Also includes support for multiple domains.

EasyMemberPro - A great membership website software tool. Includes instructional videos and will install an entire back-end to let you signup members (and affiliates) and protect files of all types (pdf, mp3, audios, videos, etc). Version 2.0 was released and new features added so grab it now. I cannot recommend EMP any longer. There was a recent outage at their licensing server which caused all membership admins to be invalid.

caribou cms - A low cost monthly payment (or single payment) Membership Management system (Content Management System) that handles affiliate tracking, coupons, and multiple payment processors. A great choice for just 'trying out your idea'.

AutoRun Typhoon - Bundle your files into one Autorun (.exe) file for protection. Combine this with Multimedia Protector (below) for the highest security (locked to a single computer).

Mirage Systems - Makers of Multimedia Protector and License Protector. Use these two software applications to lock any type of file, or program application to a specific computer. The highest security available for your files/applications.

Simple Member - Another Membership option, but lacking in some areas.

The Membership Script - Claims to 'do it all', but can be pricey.

Sitelok - excellent site protection software which also has options to setup a membership website. Up to 50 custom profile fields can be defined and a integration plugin for PayPal is available.

John's Little Script - John Delavera orignally sold this excellent script for protecting content.  He's not longer offering it, but some of his resellers are, and it's a great deal for $47.00. Completely lock someone out of any area of your website, requiring a username/password and integrates automatically with PayPal, ClickBank and 2Checkout.  Help videos included too.

DPD - a great Digital Product Download protection website offering protection of digital products for a flat rate every month. Also has the ability to setup/manage affiliates with no additional charge.

DigiVendorPRO - An excellent choice for selling a digital product, if you only require PayPal as your payment option. Let's you easily hide your product securely outside of your website.

DLGuard - One of the better membership software management scripts available. Supports all major payment processors (over 15 at the present time).

CBProtect - a great way to fully protect Click Bank content, PDF files, and just about anything else. The file is locked uniquely to your users computer, it cannot be stolen. Check it out and compare it to other protection mechanisms as it does require a monthly payment to continue using it.

OpenCrypt - one of the longest running software protection applications, now
expanded to include memberships, blogs, and other features.

Locked Area - an earlier version of OpenCrypt, also comes in a free Lite version. A long list of features, but written in Perl, instead of PHP.

Directory Pass - an free open-source htaccess file handler.

HASP-SRM - Aladdin provides excellent software locking features. I've used their keys for protecting software for years.

Simple Member - Another Membership option, but lacking in some areas.

The Membership Script - Claims to 'do it all', but can be pricey.

E-Power-Wrap - Ebook software/wrapper that will let you compile your PDF files into an executable .exe file and distribute it with licensing rights required.  A lower cost protection mechanism.

WordPress Blog Protection & Security

WishList Member - I've used this plugin for WordPress and it does a great job. A community is available for working with others, and plugins have been developed that work specifically with WishList Member.  One of the best options when trying to lock down a WordPress Blog (also see DAP - Digital Access Pass).

DAP - Digital Access Pass - A great protection software script. It can protect a standard website (folder or directory) or it can work within WordPress as a plugin to lock down an entire blog. Built in autoresponder and affiliate system, upselling, and online store system and forum integration is also available.

Your Member - A WordPress plugin for integrating Membership websites, also features coupons and protected RSS feed access.