These are statistics about the frequency of letters in several
languages. They should be taken with some care, since the results
depend on the sample that was used, the characters that are
assimilated (e.g, is é the same letter as e, ê and è in
French?). However, these stats are useful to break cryptographic
algorithms.

**English**
E 12.4% H 6.5% U 2.7% G 2.0% K 0.7%
T 8.9% S 6.2% M 2.5% Y 2.0% Q 0.1%
A 8.0% R 6.1% W 2.3% P 1.6% X 0.1%
O 7.6% D 4.6% C 2.2% B 1.3% J 0.1%
N 7.0% L 3.6% F 2.2% V 0.8% Z 0.0%
I 6.7%

**French**
E 16.7% T 7.3% C 3.5% G 1.1% J 0.3%
S 8.2% O 5.8% P 3.0% Q 1.1% Y 0.2%
A 8.0% U 5.5% M 2.9% B 0.7% Z 0.2%
N 7.9% L 4.9% V 1.4% X 0.6% K 0.1%
I 7.6% D 3.9% F 1.2% H 0.5% W 0.0%
R 7.4%

**German**
E 18.0% T 5.7% G 3.2% F 1.6% P 0.8%
N 10.6% D 5.4% O 2.7% W 1.5% J 0.3%
I 8.1% U 4.6% C 2.7% K 1.3% Y 0.0%
R 7.2% H 4.1% M 2.3% Z 1.1% X 0.0%
S 6.9% L 3.3% B 1.7% V 0.9% Q 0.0%
A 6.0%

**Italian**
E 11.7% R 7.0% P 2.8% F 1.1% K 0.0%
A 11.7% L 6.2% U 2.7% B 1.1% J 0.0%
I 11.3% S 5.1% M 2.5% Z 0.9% Y 0.0%
O 8.7% C 4.1% G 2.0% H 0.9% W 0.0%
T 7.2% D 3.9% V 1.8% Q 0.4% X 0.0%
N 7.1%

**Japanese**
Listing the frequency of all Japanese characters would be rather
long and boring, so here are the top 20 most common kanji (chinese
characters), along with their (very approximate) meaning. Many thanks to tres equis who provided me with the HTML entities for Unicode characters. You may need Japanese fonts to see them.

日 day, sun 1.43 % 本 book, origin 0.72 %
一 one 1.21 % 長 long 0.60 %
十 ten 1.08 % 中 middle 0.59 %
二 two 0.95 % 五 five 0.55 %
人 human 0.93 % 出 get out 0.54 %
大 big 0.93 % 事 fact 0.50 %
年 year 0.92 % 社 shinto, company 0.49 %
会 meet 0.91 % 市 town 0.49 %
国 country 0.85 % 者 person 0.49 %
三 three 0.74 % 月 month, moon 0.48 %

In Japanese, the 1000 highest-frequency kanji correspond to
almost 95% of all use. That percentage is 99% for the 1600
highest-frequency kanji, and 99.9% for the 2400 highest-frequency
kanji.

**Latin**
I 10.1% S 6.8% C 3.3% Q 1.3% H 0.5%
E 9.2% R 6.8% P 3.0% B 1.2% J 0.0%
U 7.4% N 6.0% L 2.1% F 0.9% K 0.0%
T 7.2% O 4.4% D 1.7% V 0.7% Y 0.0%
A 7.2% M 3.4% G 1.4% X 0.6% Z 0.0%

**Perl**
I wish I had statistics about Perl...

**Portuguese**
E 12.1% N 6.5% U 3.3% F 1.1% X 0.4%
A 11.9% T 5.9% P 3.0% B 1.0% J 0.3%
O 11.1% C 5.1% L 2.8% Q 0.8% W 0.1%
S 7.6% D 4.2% V 1.6% H 0.7% Y 0.0%
I 7.3% M 3.8% G 1.6% Z 0.5% K 0.0%
R 7.3%

**Spanish**
E 13.0% S 6.9% U 3.6% V 1.0% J 0.3%
A 11.1% T 5.3% P 3.0% F 0.8% Z 0.3%
O 9.7% C 5.2% M 2.9% Y 0.7% X 0.2%
I 8.2% D 4.5% G 1.4% H 0.6% W 0.1%
N 8.0% L 3.6% B 1.3% Q 0.6% K 0.0%
R 7.7%

Many sources:

http://www.arachnaut.org/archive/freq.html

http://www.fortunecity.com/skyscraper/coding/379/lesson7.htm

http://lists.village.virginia.edu/lists_archive/Humanist/v14/0240.html, cached by Google

http://nozaki-lab.ics.aichi-edu.ac.jp/nozaki/asahi/kanji.html