how do you do a newsletter (batches)

[eluser]tomdelonge[/eluser]
I don't want to use something like mailchimp. I want to make something myself. Say you have 100 subscriptions. Can you think of a way maybe to have each page visit do 5 or something? Until the list is empty? I don't know if it would be slow or not to check the database every page view to see if any subscriptions are pending.

Any ideas?