Y.Kohno

This is a flexible search form widget. 
You can easily generate a multi condition search form and display anywhere as widget.
複数のカスタムフィールド、投稿タイプ、カテゴリー、タグでの検索が可能な複合検索フォームを簡単作成できるプラグイン。ウィジェットで好きな場所に設置可能。
Currently supports 
– Custom Fields 
– Taxonomies 
– Categories 
– Post tags 
– Post Type

WP Meta Search

Search form for searching through custom fields, post types, categories, tags, and free text.

Post Status Scheduler allows for scheduling of post status changes, category/tag adding or removing and 
removing of postmeta on any given date or time. It can be activated on any post type and shows 
up on the post edit screen in the publish section. From version 1.0.0 it has a feature for sending 
an email notification to the post author on the scheduled update.
<h4>Shortcodes</h4>
<ul>
<li>[pss_scheduled_time post_id=””] can be used to get the post’s scheduled date and time.</li>
</ul>
<h4>Filters</h4>
Scheduled Update: 
* post_status_scheduler_before_execution 
* post_status_scheduler_after_execution
Email Notification ( version 1.0.0 ): 
* post_status_scheduler_email_notification_recipient_email 
* post_status_scheduler_email_notification_subject 
* post_status_scheduler_email_notification_date 
* post_status_scheduler_email_notification_body

Post Status Scheduler

Change status, categories/tags or postmeta of any post type at a scheduled timestamp.

WP Meta Search vs Post Status Scheduler