More Discussions for this daf
1. Emes v'Yatziv d'Oraisa 2. Ba'al Keri and reciting Torah 3. Berachos mid'Oraisa
4. Difficult Kal v'Chomer 5. Tevillah for Ba'alas Keri 6. Interrupting in Middle of Tefilah
7. Davening long 8. Rebbi Yochanan 9. Rebbi Yochanan's Kal va'Chomer
10. Correction to Point by Point 11. Emes at the end of Keri'as Shema 12. Praying twice, twice
13. Using a Verse for Multiple Purposes 14. Anusas Aviv 15. Bending when the Tzibur gets to Modim
16. Tefilah on Shabbos 17. Tefilas Nedavah 18. Semuchim
19. Malchus 20. Shemoni Esrei with Tzibur 21. shema or emes viyatziv being derabanan or deoraysa

Bruce Neal asked:

Is the Shemonah Esray the only Free Will Offering or Korban Nedavah? Or are there other such offerings we can do in prayer?

The Kollel replies:

Certainly a person may offer his own "freewill" prayers. According to Jewish law, however, he should not recite the full name of Hash-m in his private, personal prayer, because only the legislative body of the Sanhedrin has the prerogative to institute a prayer with the name of Hash-m.

The reason why we only find the term "freewill offering" being used with regard to the Shemoneh Esreh is because the Shemoneh Esreh was instituted to correspond to the offerings that were brought in the Beis ha'Mikdash, as the Gemara explains on Daf 26b (the morning Shemoneh Esreh corresponds to the morning Tamid offering; the afternoon Shemoneh Esreh corresponds to the afternoon Tamid offering; and the nighttime Shemoneh Esreh corresponds to the limbs and fats that were burned upon the altar during the night). Since the Shemoneh Esreh corresponds to the offerings, the Sages discussed the concept of a "freewill" Shemoneh Esreh in place of a freewill sacrificial offering.