The (Hebrew) Wikipedia entry on "chiddush" has a chart that lists 20 such instances in Shas where the principle of "chiddush"is invoked.
NOTE: for English translation of this list, please see below said image
1) חיוב קרבן בשבועת ביטוי - an “oath of expression” about a future or past event (ie NOT an oath of testimony)
- chiddush- a negative commandment that isn't punishable by kareis requires a korban (see Shevuot 26b with Tosfos)
2) בשר בחלב - meat and milk
- chiddush-
a) 2 individually permitted things together are forbidden
b)the prohibition is just in the cooking of them together- ie if one were to soak meat in milk it would be fine (see Pesachim 44b)
3) גיעולי עובדי כוכבים - purging the vessels of non-Jews with boiling water
- chiddush- usually a utensil which imparts a bad flavor to food is permitted. However by vessels of non-Jews, even if the vessels impart a bad flavor the food is still prohibited
(see Pesachim 44b)
4) קנס - paying a penalty
- chiddush- Paying despite being killed (see Ketubot 38b)
5) נזיר - an instance of accepting a nazirite vow upon oneself
- chiddush- if a person says he's a nazir from grape seeds (ie accepting a partial nazirite vow upon himself) he's a full nazir (see Nazir 3b-4a)
6) שפחה כנענית לעבד עברי - Canaanite maidservant to a Jewish slave
- chiddush- a Jewish male is permitted to marry a non-Jewish woman (see Kiddushin 21b with Rashi)
7) אשת יפת תואר - a beautiful woman who was taken captive in war
- chiddush- a non-Jewish woman is permitted to a Jew (inferred from Kiddushin 21b)
8) עדים זוממים - conspiring witnesses
- chiddush- we rely on the 2nd set of witnesses (see Sanhedrin 27a)
9) ריבית - charging interest
- chiddush- the borrower who loses money also violates a prohibition (see Bava Metzia 61a)
10) טומאת שרץ - if a sheretz (creepy crawly creature) imparts "flavor" to a mixture it is still prohibited
- chiddush- even though it's gross & imparts flavor to the detriment of the mixture (and should thus be permitted) it's still forbidden. (see Avodah Zarah 68b)
11) טומאת שכבת זרע - impurity of an emission that's imparted into a mixture is still prohibited
12) זרוע של איל נזיר - the foreleg of the ram offering that a nazirite must bring
- chiddush- it's permitted to nullify a prohibited item even from the outset (lchatchilah)
(see Chullin 98b)
13) חלב בהמה טהורה - permissibility of consuming milk from a kosher animal
- chiddush - milk originates from the blood (akin to ever min hachai) and yet the Torah still permits it (see Bechoros 6a-b)
14) צרעת הבתים - leprosy on houses
15) יבמה - the widow of a childless man who has brothers
- chiddush- an ervah (ie brother's wife) is permitted (see Yevamos 17b)
16) נבלת עוף טהור - the carcass of a pure bird
- chiddush- rather than by touching or carrying, one contracts tumah by eating the carcass of a pure-- ie kosher-- bird (see Zevachim 70a)
17) מנחת העומר - the Omer offering
- chiddush- a korban of barley is brought (inferred from Menachos 5a-b)
18) טומאת בעלי קרי בהר סיני - the impurity of a person who had an emission by Har Sinai
- chiddush- in this instance the Torah is more stringent with a baal keri than with a zav or a metzora (see Niddah 42a)
19) מזיד בשבועת ביטוי - purposely taking a shevuas bitui
- chiddush- a person purposely taking a shevuas bitui (ie “oath of expression”- NOT an oath of testimony) is obligated to bring a korban (see Shevuot 37a)
20) מוציא שם רע - a man who claims his wife committed adultery
- chiddush- if the woman is guilty of the motzi shem ra claim against her she is executed by stoning- despite the fact that if she were to commit the sin in her current state (ie as a regular married woman without a motzi shem ra claim) she would be executed via strangulation
(see Ketubot 45a)
