From the project website:
The M4 Project is an effort to break 3 original Enigma messages with the help of distributed computing. The signals were intercepted in the North Atlantic in 1942 and are believed to be unbroken. Ralph Erskine has presented the intercepts in a letter to the journal Cryptologia. The signals were presumably enciphered with the four rotor Enigma M4 - hence the name of the project.
The first message has already been successfully broken. The plain-text reads:
1930 Funkspruch 1851/19/252:
" F T 1132/19 Inhalt:
Bei Angriff unter Wasser gedrückt.
Wabos. Letzter Gegnerstand 0830 Uhr
AJ 9863, 220 Grad, 8 sm. Stosse nach.
14 mb. fällt, NNO 4, Sicht 10.
1930 Radio signal 1851/19/252:
" F T 1132/19 contents:
Forced to submerge during attack.
Depth charges. Last enemy position 0830h
AJ 9863, [course] 220 degrees, [speed] 8 knots. [I am] following [the enemy].
[barometer] falls 14 mb, [wind] nor-nor-east, [force] 4, visibility 10 [nautical miles].
Hm, digging in the past with modern technology...
(via Network Security Blog)