Free Software Magazine: "Smail is simple, clean and efficient. Although it is as secure as pretty much most of its larger cousins (it’s been the subject of just one security advisory), it has arguably one of the least cumbersome configuration set-ups around.

Its small size and simple configuration make it a great replacement for the bigger MTAs — especially Sendmail — in situations where you just don’t have the time/energy/patience to get involved with configuring an MTA."