Useful Tools 
Found something promising: mutt has been ported to
cygwin. It works out of the box, too, with cygwin's gpg. The only security problem present appears to be that the submission agent,
ssmtp, does not do TLS out of the box and the source code won't build:
ssmtp.o(.text+0x1c01): In function `smtp_open':
/usr/src/ssmtp-2.60.9-1/ssmtp.c:1119: undefined reference to `_X509_free'
collect2: ld returned 1 exit status
make: *** [ssmtp] Error 1
Looks like it might be a SSL version problem.