Some features of each would be:
- Purchasing access to a hidden forum.
- Purchasing access to special forum features. (Ranks, Usergroups, Name/Title changes, etc.)
- Purchasing access to special downloads.
- Automatic recurring charges.
- Automatic user group adjustments when purchased and when expired etc.
- Same as above, but as one-time payments rather than recurring subscriptions.
- A donation bar/goal to be displayed on the forum somewhere.
- Perks for donations such as putting users in a donation user group automatically.
- Perks for donations such as giving users the ability to change their name or title.
There are tons of payment endpoints that can be added and expanded on, some of the most common being:
A lot of custom features could be implemented into this as mini-plugins to the payment system as well. Custom forum setups could have all kinds of fun things like buying permissions, buying all kinds of postbit modifications, the ability to post certain things like images/html, etc.
Endless features and possibilities could come from a system like this.