My second small contribution to Open Source (first was in the year 2004 for CMS Typo3).
The utility for exporting of Netflow network statistics (from files collected by flow-tools) to PostgreSQL database. Export is made at the very low level (binary tuples that are going to database formed in a multithreaded C code), so it works really fast and, the same time, it is transactional.
Written in the year 2008. Last time I shaked off the dust from this was year 2010.