http://www.factmonster.com/ipka/A0903395.htmlyw
lists two more:

“Silent e helps a vowel say its name.”

“When two vowels go walking, the first one does the talking”

Ah que saudades! A escola–eu a adorei!

The rule we learned as children in school was “I before E except after C” but I discovered there is more to the rule, and the complete rule accounts for many of the exceptions:

http://www.spelling.org/Books/Mastering_I_before_E.htm

vein, science, Einstein, sufficient, neither, weird, plus about two hundred or so more. So why bother with it? The answer is simply, don’t bother with half a rule. If you learn the whole rule you will find out that it does work 99.9999% of the time!

This book presents the rule and then very slowly and methodically teaches the meaning of each part. What the author found out when he first taught this rule to junior high students at the Flint Alternative Junior High School is that they really didn’t understand the meaning of the word except.

So he not only had the students memorize the ENTIRE RULE, but he also developed exercises in which the students had to give the reason for their answers.

Here is the Complete Rule

Examples that follow the rule

Use I before E ie = believe, field, yield, priest, shield
Except after C cei=receive, receipt, conceited, conceive
Or when sounded as “I” as in Einstein “I” = ei Eileen, height, sleight, stein, Einstein
Or “A” as in weigh “A” = ei weigh, weight, neighbor, sleigh, heir, their
Neither, weird, foreign, leisure “X” = ei either, weirdo, foreigner
Seize, forfeit, and height “X” = ei seizure, forfeiture, protein, caffeine, heifer
Are the common exceptions spelled right
But don’t let the C-I-E-N words get you uptight! cien = cien!=science, efficient, sufficient, conscience, ancient,

Remember the words we said didn’t follow the rule? They do follow the complete rule.
Here they are: vein, science, Einstein, sufficient, neither, weird.

Correctly applying the rule means:

vein is ei because it sounds as “A”
science is ie because it is a cien word. (Note: We don’t have any cein words)
Einstein has ei’s because both sound as “I”
sufficient is ie because it is a cien word.
neither is ei because it is a common exception
weird is ei because it is a common exception

Não sei se posso afirmar isso, mas a observação foi interessante. Obrigado!

See you!