WordPress.org

Will my monster be the same on different blogs?

Yes, if they're using the standard version (and I didn't mess up anything).

Can it generate monsters only for people without gravatars?

Yes. Just turn on the Gravatar option in the MonsterID options.

Can I add MonsterIDs to the Recent Comments Widget in my sidebar?

Yes, this plugin provides a replacement widget to Recent Comments (since the default widget doesn't provide the commenter's email).

Why should I use this plugin when Gravatars now has Identicons?

The gravatar monsters are pretty good but if you want artistic monsters or just want one set of avatars for everyone on your site, then this plugin's for you. Otherwise, sure go with gravatars (just set &default=monsterid in the gravatar url).