The Baconian cipher, despite having nothing to do with bacon, is a delightful means of hiding and encrypting one message within another. Firstly, convert all the letters in a secret message using the table below (I prefer the second version of Bacon's cipher as it uses all twenty six letters of the English alphabet). Then create a plain text message that has at least five times the number of letters as the secret message. Finally, using the converted secret message, change the typeface of the plain text message so that all the letters which correspond to “0” are of one type (like this), and all the letters which correspond to “1” are of a different type (like this).
A
B
C
D
E
F
G
H
I
J
K
L
M
00000
00001
00010
00011
00100
00101
00110
00111
01000
01001
01010
01011
01100
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
01101
01110
01111
10000
10001
10010
10011
10100
10101
10110
10111
11000
11001
For example, let's take “hello” as our secret message and convert it to:
00111 00100 01011 01011 01110
Using the plain text message “There is a secret message here”, we would get:
There is a secret message here.
It can be quite a subtle effect that would make for yet another fun postcard to send/receive.