Add Download Link to Order Confirmation Page

How can I display download links for any purchased products on Order Confirmation Page?

Right now, it doesn't make any reference to the download link at all. User's must wait for an email, which in some cases can be notoriously slow (*cough* Go Daddy *cough*). I'd like to make it a little more obvious to the enduser and, hopefully, limit the number of inquiries/complaints the merchant receives.