MacGyver

Her trick

The office's most resourceful paranoiac, she installs every tool possible to secure her data, from laptop drive encryption to booby-trapped boot CDs with drive-wiping scripts. The most benign information is triple-encrypted and obscurely stored, and backup is regarded as an excessive security exposure. Work in her group grinds to a halt during vacation as they discover locked files and blocked processes, fomenting hard feelings among her coworkers about even basic security.

Your treat

Work with management to compartmentalize her work into a single "silo" in order to minimize work process impact when she's gone -- or present. Provide an outlet for encrypted overkill by diverting her attention to a special security project, alpha testing new security technologies on "company secrets" (test data). Better yet, make her a team lead on a corporate extranet PKI project -- the Big Dig of security -- and you'll never hear from her again.