What tools do you or your company use to schedule emails?

I think its just too insane to query the db X mins just to check if there are any scheduled emails to send out.

I also think its too heavy to create your own scheduler just for a simple scheduling feature. And I feel the application will bloat up adding such a relatively big implementation for such small task. And you will also need to handle another workflow when the server restarts (intentional upgrades of server for example)

What tools are you all using? Ideally a free service or some reasonably priced service that will do this scheduling for you. And you can just use it via API.

CHEERS from Singapore!