I'd like to buy bitcoins via SEPA deposit automatically with a recurring schedule. To specify this with an example, I would like to purchase bitcoins for 100 EUR each month, at the current market rate, without manual intervention. For this, I can set up a recurring payment at my bank to a SEPA bank account. The manual way to do this at Bitstamp would be:

• Start SEPA deposit at Bitstamp for 100 EUR.
• Make a bank transfer to the given account with the given message.
• Wait for funds to appear at Bitstamp.
• Use instant order to purchase bitcoin for 100 EUR (converted to dollars).
• Wait for the transaction to complete (may take days if market fluctuates).
• Withdraw bitcoin from Bitstamp to a given address.

I am not afraid to run a server, or to create my own program using an API to do this. I am not willing to use screen scraping however, because I would wish for this to run with minimal intervention and such an approach would seem too error prone. I am also obviously not able to affect my bank, so the best I can do is to have a recurring payment with a fixed message/reference number each month.