Gmail has recently provided a innovative feature to help users who are annoyed of sending a particular message again and again. The feature called “Canned responses” can be set in the following way.

Go to Settings-> Filter-> Enable Canned Responses

Compose a new message.

Select New canned response… and give a name to the response in the text box.

Go to Settings->Filters.

Create a New Filter using the Search Criteria provided.

Choose a Canned response that you created ( in the previous image ).

Create the filter and you are done.

Now you can send a reply message on fly by just choosing the Canned response while composing the message.

For automatic mail delivery to certain users, create filters on them as described above.