Warn/Die Plugin
The "Warn/Die" plugin lets you control the Movable Type build process. The 'MTWarn' tag lets you output messages from your templates during the build process. These messages might be used for debugging purposes or might just be informational. The 'MTDie' tag lets you halt the build process.
Availability
You can download this plugin from here: mtwarndie-1_0.zip
Examples
<MTWarn>Building Entry: <MTEntryTitle></MTWarn>
or how about... (using my IfEmpty plugin)
<MTIfEmpty var="EntryMore">
<MTDie>This blog requires an extended entry.</MTDie>
</MTIfEmpty>
The link to download this doesn't work.
Oops-- the link has been fixed. Thanks, Kyle.