I do not pray in tongues, but I learned to "speak in tongues" just to satisfy my own curiosity that it was nothing but a physical ability and, essentially a misguided power play by the church.
My experience was at ICA in Hong Kong, an AOG church, I was at the Alpha course "Away Weekend" and there had been a lot of talk about tongues. It was a mark of pride, a sign of "spiritual maturity" which to me (and given the characters of the people that did it) meant it was a load of nonsense. There was such a false humility in the humility in which the tongue-speakers had, they used it so glibly as if to show how easy it was to them, which only caused the others to marvel more.
One girl in particular convinced me there was something wrong with this - because she WANTED it, so bad! She was almost crying at dinner, she said "why didn't God give me this gift?" And the slightly superior church lady was at her side, "there there, we all have different gifts [but mine is better than yours]."
So, curiosity aroused, hen I got back I researched it, delved into glossolalia, found it was something quite easy to learn to do, one of those little tricks like learning to whistle or blow bubble gum, that you always feel faintly foolish practicing alone but the payoffs when back in company are huge
It's really no big deal, take away the spiritual mulch, I did it pretty well in about two minutes. It's quite fun, quite novel - and if I'd been surrounded by people in awe and praising the Lord I am sure I would have found it a spiritual experience..... but I think if everybody knew how easy it was, the myth would dissolve and nobody would bother doing it.
Anyway, there are some who say it's the genuine Holy Spirit and I would never take that away from them or even disagree or debate with them - I am sure there are genuine cases, but I also think it's become a thing, a power play, an attraction or amusement ride to give the kids or newcomers something to aim at. Not far off the spiritual maturity games played by LSM, come to think of it.
I was gonna post a scientific study I found a while back but it would break copyright.
A Linguistic Analysis of Glossolalia by Michael Motley, Communication Quarterly Vol 30, No. 1, Winter 1981. It found that there was significant language structure within "tongues" speaking, not related to speakers' own language and likely not coming from traditionally understood cognitive centres. The implications of that study were for language learning, they weren't examining it from the spiritual side - but that's an interesting finding and adds credence to those who would say it is from the Holy Spirit. Certainly according to those findings tongue speaking is not "made up" and is coming from somewhere deeper than the brain which controls normal language/speech. That defeats my own point somewhat but I think it's interesting - and hiding knowledge which disagrees with one's arguments is never a good strategy