Mutt

mutt is an alternative MUA (Mail user agent) also known as mail client, for UBOs. It also as a windows version apparently which "may require cygwin. Mutt is not for the faint of heart, it has one of the steepest learning curves for an MUA, but as a result it's one of the most powerful and configurable.

.muttrc

# This will prevent your read email from being moved to another folder.
set move="no"
# Change my From: header
my_hdr From: me@example.com
set from="\"John Doe\" <me@example.com>"
set use_from
# To be able to edit headers inline:
set edit_headers="yes"
# browse through multiple mailboxes with "tab"
# and 'c' keys, that way you can have procmail sort your mail
# and you just let mutt select through them...
mailboxes /var/mail/dog ~/Mail/OpenBSD-bugs ~/Mail/OpenBSD-cvs

External reading

Mutt manual