See here for example: http://cryptome.org/cia-decrypt.htm

There was a released-but-redacted CIA memo saying, "An Egyptian Islamic Jihad (EIJ) operative told an XXXXXXXX service at the same time..." From analysis of the size and shape of the blob, the missing text could only be "Egyptian".

In fact, a monospace font turns out to be harder for this; with a proportional font, as here, there is more variability in total word length due to the different letter widths, and so a greater ability to reduce the number of possible matches.