1. Shmuel says that the law follows the view of Rebbi Eliezer in four cases in Seder Taharos.
2. Rebbi Yehudah ben Bava "testified" about the proper Halachah in five cases.
3. There is a dispute about Ma'ariv on Motza'i Yom Kippur.
4. Rebbi Chiya: It is beneficial for a woman to have a lot of menstrual bleeding.
5. A woman is clearly considered pregnant once she is three months into her pregnancy.
A BIT MORE
1. The Gemara proves this by citing cases of Mi'un and Chalah in which the Halachah clearly follows the opinion of Rebbi Eliezer, despite the fact that these cases were not included in the four cases mentioned earlier.
2. These include Halachos such as instructing a minor to do Mi'un, allowing a woman to remarry based on the testimony of one witness, and that a rooster who killed a person is put to death.
3. Tana Kama: One recites the first three and last three Berachos of the Shemoneh Esreh, and between them one should say Havinenu (an abridged version of the Shemoneh Esreh). Rebbi Chanina ben Gamliel: One recites the regular weekday Shemoneh Esreh so that he can recite Havdalah ("Atah Chonantanu") in the blessing of "Chonen ha'Da'as."
4. Rebbi Meir: If a woman has heavy bleeding during her periods, it is a sign that she will have many boys.
5. This is apparent from the verse in Bereishis (38:24) which states that people noticed that Tamar was pregnant when she was three months pregnant.