Magic Mail Monitor is a POP3 email notification tool.

The latest version has the following primary features:

easy to learn explorer-like user interface
unlimited number of maildrops
thorough status reporting
secure information storing
secure authentication supported via APOP
custom notifications per each mailbox
MCI device playback notification
shell open command notification
pop-up message notification
message header preview
time elapsed since last successful check
QuickView
QuickReply
QuickSend
QuickDelete
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On-line help

More info:
hxxp://www.geeba.org/magic/