PayPal Recurring Payments for WordPress
It turns out that adding recurring payments or subscriptions to the paypal payments standard is a doddle. The only qualification being that you need a Business or Premier account.
The Quick PayPal Payments plugin admin view is simple:
Just select the field, edit the payment settings and update the form. Nothing more to do.
If you want recurring payments or subscriptions and have a Business or Premier PayPal account get in contact and I can send you the update for testing.
For those who want to do it themselves this is the paypal guide.
And here are all the variables.