UnDBX (portable)

Tool to extract, recover and undelete e-mail messages from Outlook Express .DBX files. 

On first run all messages are extracted as individual .EML files. Subsequent runs only update the output directory with new messages, and delete old .EML files that correspond to deleted messages in the .DBX file. Corrupted .DBX files (including files larger than 2GB) can be opened in recovery mode, in order to recover messages and partially undelete deleted messages. The success of recovery depends on the type and level of .DBX file corruption.

http://code.google.com/p/undbx/

McAfee Stinger (portable)

McAfee Stinger removes 6,000 common viruses and 'fake alert' malware on-demand. It is not a replacement for a full antivirus, but handy in many situations. McAfee Stinger is freeware for personal and business use and requires admin rights.

McAfee Stinger detects and removes prevalent Fake Alert malware and threats identified in the "List Viruses" section of the Stinger application. While not a replacement for full fledged antivirus software, Stinger is updated multiple times a week to include detection for newer Fake Alert variants and prevalent viruses.

http://portableapps.com/apps/security/mcafee-stinger-portable