File structure and naming convention

My company is converting to DITA with no CMS (for now).  We are creating a file structure and naming convention and are looking for some best practices to guide us.  We have approximately 10 functional groups of content.  To maximize reuse of topics and to make searching for topics easier, we are wondering if our naming convention should use suffixes or prefixes.  For example if I have sets of task to teach users how to build models should my naming convention begin or end with the t for task (and does this really matter?): t_model_building.dita or model_building_t.dita. Focus Areas: BPEL | DITA | ebXML | IDtrust | OpenDocument | SAML | UBL | UDDI
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