What is the word similar to “Bingo” or “Hallelujah”, used by Greeks, in modern Greek?

To add some further nuances:

• When an interlocutor has finally understood something we’ve been hinting at—one of the contexts “Bingo!” is used in English—Greek uses α μπράβο! “Ah, well done”, with the emphasis on the “ah”. Kind of like “there you go”.
• More exasperated variants of “finally! at last!” (Dimitrios Michmizos’ answer) are έλεος! “Mercy!”, or its Turkish equivalent νισάφι < ınsaf.
• An expression of relief at something that has dragged on (which is the likeliest experience after a long installation) is ουφ! “phew!”, or αμάν πια! “alas already!”