Arvind Satyatanarayan, author of Movalog and creator of MT-Blogroll, has released a new Movable Type plugin - MT-Protect - which allows you to protect individual weblog entries via password or via a Typekey identity. This plugin may prove especially useful for those wanting to charge for access, or to restrict access in some way, to specific parts of their blog.
Arvind has also initiated a Drop-Cash campaign to help support his efforts as a developer for this plugin. Even if you don't plan to use the Protect plugin, I encourage you to make a donation, now! Arvind has spent several hundreds of hours providing useful tips, hacks, and plugins for the Movable Type community. I believe that what he is asking for only represents a part of what it actually costs to run Movalog on a monthly basis. Be generous and help support the MT developer community!