Bee Free will automatically allow you to manually email any document by clicking on the [email] link at the top of the document. This also applies to reminders where you can email hundreds of reminder letters with the click of a button.
To do this you need to be on the 'medium' package of higher. The basic or small packages will not allow mass mail outs.
Go to administration >> reminders.
Select the reminder category, tick all the reminders and then click print
Select the letter.
Click on the [email] link at the top of the print preview.