My website has: - Shopping cart for selling our software and support products. - Forums for discussing our software. Email notifications are available for use

My website has: - Shopping cart for selling our software and support products. - Forums for discussing our software. Email notifications are available for users who want to follow threads. - Ticket tracker for reporting bugs and making support requests about our software. Email notifications are, once again, available for users to follow threads. - License manager, so that people who have bought our software can get the keys to download the software. How would you suggest we accomplish those tasks without having a sign-in, at all?