The heartbeat behind tongues is evangelism. Notice:
Acts 2
[4] And they were all filled with the Holy Ghost, and began to speak with other tongues, as the Spirit gave them utterance.
[5] And there were dwelling at Jerusalem Jews, devout men, out of every nation under heaven.
[6] Now when this was noised abroad, the multitude came together, and were confounded, because that every man heard them speak in his own language.
Notice the word "tongues" and the word "languages" are interchangable.
[7] And they were all amazed and marvelled, saying one to another, Behold, are not all these which speak Galilaeans?
Galilaens were not great multilingual scholars, they were fishermen. How could they speak other tongues/languages?
[8] And how hear we every man in our own tongue, wherein we were born?
[9] Parthians, and Medes, and Elamites, and the dwellers in Mesopotamia, and in Judaea, and Cappadocia, in Pontus, and Asia,
[10] Phrygia, and Pamphylia, in Egypt, and in the parts of Libya about Cyrene, and strangers of Rome, Jews and proselytes,
[11] Cretes and Arabians, we do hear them speak in our tongues the wonderful works of God.
Clearly, this was an evangelistic gift, given to these believers to reach the great multitude visiting Jerusalem in their "mother tongues."
God does not need ecstatic communications. God doesn't need us to move our mouth at all, we can speak to him from our hearts in utter silence. These men, however, needed to hear, as it says in verse 11, the wonderful works of God.
I would also like to point out, tongues is a hearing gift as well as a speaking gift because the unbelieving Jews heard gibberish:
[13] Others mocking said, These men are full of new wine.
[14] But Peter, standing up with the eleven, lifted up his voice, and said unto them, Ye men of Judaea, and all ye that dwell at Jerusalem, be this known unto you, and hearken to my words:
[15] For these are not drunken, as ye suppose, seeing it is but the third hour of the day.
Actually, they were preaching. That is what the New Testament word prophesying means;
[16] But this is that which was spoken by the prophet Joel;
[17] And it shall come to pass in the last days, saith God,I will pour out of my Spirit upon all flesh: and your sons and your daughters shall prophesy, and your young men shall see visions, and your old men shall dream dreams:
I am not so dispensationalist that I don't believe tongues does not still happen, I just don't think it what we see in modern pracitce, ESPECIALLY, when we see it being used in foreign lands in a biblical way...to win souls.