KDETools Outlook PST Merge - KDETools PST merge tool can add multiple PST file into a new or existing Outlook data file (PST).
Vsoftware.org vMail - vMail PST to MBOX Converter exports emails from Outlook PST file to MBOX folder for Apple Mail, Thunderbird, Spicebird, SeaMonkey & Netscape email client
GainTools PST to MBOX Converter - Convert Outlook PST Files to MBOX format for accessing emails in other emails clients.
Regain PST to MBOX Converter - Easiest way to convert Outlook PST to MBOX file format.
KDETools EML to PST Converter - KDETools EML to PST Converter is the best tool for convert EML/EMLX files to Outlook PST, Office...
VOOK MBOX to PST Converter - MBOX to PST Converter extracts mailbox data and import to Outlook PST. It is capable to migrate Thunderbird to Outlook PST format & export mailbox items.