ISPBill is an ISP billing and management system. It features automatic generation and emailing of invoices, receipts and statements, a customer interface, a ticket system, and much more. ISPBill is intended to continue where cwispy left off.
MyInvoice is a simple php/mysql based invoicing system aimed at freelancers and small businesses. It allows the user to manage clients/invoices, clients to log in to view and print invoices, and also features automatic email notifications.