Requires iOS 3.2 or higher

Mail Rules is an extension that can apply rules to new mail as it arrives.

It is accessed via the "Rules..." page in Mail, Contacts, Calendars settings.

Supports matching on the following criteria:
- Account
- Header
- Recipient
- Sender
- Subject
- Has/has not been read
- Location
- Time
- Day

And supports the following actions:
- Display a notification (iOS4+)
- Play a sound
- Vibrate
- Delete message
- Mark as read/unread
- Mark as flagged/unflagged
- Copy/Move to folder
- Run a command
- Stop processing rules
- Suppress new mail sound
- Highlight
- Repeat

No new icons are added to your home screen, you can configure options from the Mail>Rules panel in your Settings app.

See More Info below for Screenshots