I am presently using a open source product called Myclientbase (invoice software), I had a programmer create a calendar module for this product that does not work 100 percent, I need to have this module corrected and add some enhancements added, based on the fullcalendar code located on the web (open source).
For the future I am also looking for someone interested in making client side modules related to accounting and calendars. Myclientbase is an invoice software package (open source) that allows for modules to be used for the administrator and there is also the option of clients logging on to see their invoice information etc. I would like development in this area.