With this module you're able to create and administer invoices.
The module creates an invoice node type. The module can be used in combination with the pathauto module to auto generate the title.
PDF document
It's possible to view the invoice as full node view on your site, as html print view and as pdf document. The nice dompdf library is used to generate pdf documents. The library is not included into this module. You'll have to download it yourself and paste the dompdf folder into the root of this module. so you'll get "sites/all/modules/invoice/dompdf".
The library can be downloaded from the official site, but has not the nice Arial font included by default. Fortunately, according to the End User License Agreement of Microsoft I have the right to redistribute Microsoft core fonts in unaltered form. So I already included the Arial font into the dompdf package.
The DataSync module was written to schedule and execute jobs and import data in a much more scalable and reliable way than with cron.php and hook_cron. It allows you to schedule and run module-definable types of jobs on multiple servers in a centralized way. It uses database transactions in order to ensure that no data is corrupted while running multiple jobs at the same time. DataSync keeps track of the status of jobs and what phase they are in, so that if a job fails it can intelligently decide how to proceed. Almost all of DataSync's default behavior is overridable when you create your own job types.
DataSync has run over 180,000 jobs on our production servers already.
Warning: A bug introduced in CTools 1.2 causes the DataSync scheduler ajax forms to break. Either update your CTools to the 6.x-1.3 release or apply this patch.
Some of what DataSync for Drupal 6 does:
Runs scheduled jobs at any interval or as fast as possible
Provides an interface for you to schedule and timeout jobs on certain intervals
Provides an API for you to define those jobs
Handles job errors and timeouts gracefully
Allows you to run many jobs in parallel using database transactions