Charitable - A WordPress donation plugin that gives you full control over your fundraising experience.
MakePlans - Online appointment booking - MakePlans
Revv Online Fundraising Platform - Revv is the fundraising platform that raises organizations more money.
Appointment Booking Calendar - With the Appointment Booking Calendar you can accept online bookings from a set of available time-slots in the calendar.
Give - A WordPress plugin for easily collecting donations
Dudle - Dudle is an online scheduling application, which is free and open source.