You can get the ham radio version of airmail at the following url
http://www.airmail2000.com.  The programmer is ke6rk.  This program can
be  used for all the digital modes if you have a multimode tnc.  This
program unlike the terminal programs uses data compression techniques to
send the data rates at throughput rates close to 1200 bps even though the
actual transmission rate on hf is limmited by fcc regulations to 300
bps.  Winlink also allows you to interact either using the internet or
radio links so for instance if you are mobile,  you can check email while
in an rv etc.  This service is free to hams and what you do is register
with Earl wx4j and then you periodically check on winlink just like any
other isp. 73- pat kk3f