There is a long standing custom to give money li’iluy nishmas Rebbi Meir Baal HaNess, as a way to find lost objects (see special tefila for this below) or for help in any area of life. The money should go, specifically, to help the poor of Eretz Yisroel.
The Chida says that the source for this custom is the Gemara (Avodah Zara 18a-b) where Rebbi Meir bribed a guard to release his imprisoned sister-in-law. The guard asked what happens if he’s caught and Rebbi Meir told him to say Eloka D’Meir Aneini (G-d of Meir answer me) and he would be saved, and that’s what happened. From there comes the custom of donating money or oil for the neshama of Rebbi Meir, saying Eloka D’Meir Aneini, 3 times.
Rebbi Meir Baal HaNess said he would help those that gave to the poor of Eretz Yisroel, for the sake of his neshama.
After giving tzedaka, say 3 times:
??? ??? ??????, ??? ????? ?????, ?? ?????? ???? ??? ???? ?? ??????. ?? ???, ????? ?????? ?? ????? ???? ??? ???, ???? ????? ?? ????.
???? ????? ????, ???? ????? ????, ???? ????? ????. ????? ????? ???? ???? ?????? ???? ??? ???? ??? ???, ????? ??? ?????, ????? ?? ?????? ???????
To translate:
Rabbi Binyamin said: All are in the presumed status of blind people, until The Holy One, Blessed Be He, enlightens their eyes. From here {Bereishit 21:19}
?? ?????????? ???????? ???-????????, ???????? ?????? ?????; ????????? ??????????? ???-???????, ?????, ??????????, ???-????????. And God opened her eyes, and she saw a well of water; and she went, and filled the bottle with water, and gave the lad drink.
{The derivation being that the well was always there, but Hagar did not see it. Only after praying did Hashem open her eyes and she saw what was already there.}
God of Meir, answer me. God of Meir, answer me. God of Meir, answer me.
In the merit of the charity that I give to the ascending of the soul of Rabbi Meir Baal HaNes, may his merit protect us, may I find the lost article that I lost.
The first part, of Amar Rabbi Binyamin, is a citation from Bereishis Rabba 53:14. When Rabbi Binyamin said this, he had no idea that his devar Torah would be developed into a segulah. The second part, about Rabbi Meir, has its basis in Mesechtes Avodah Zarah 18a-b.
One good part of this segulah, from the perspective of the Amar Rabbi Binyamin part, is that if one really understands what he is saying, then this leads to a transformative realization. A person thinks he is on top of things. And suddenly cannot find something. Realize that all is in the hands of Heaven. If you want to find it, pray to Hashem, as Hagar did. It is probably there, under your nose, but you just cannot see it until Hashem enables you to.
It would seem to be appropriate for an object right under your nose, or in your pile of papers. But for someone to discover your item across town and bring it to you, for example — well, this is not really the same as being bechezkas sumin. That is not blindness, but actual recovery of what was lost. But perhaps by extension.
The second part, Elaka DeMeir Aneini also has basis, as mentioned above, in Avodah Zarah 18a-b. The gemara there reads:
?????? ?????? ??’ ???? ????? ??’ ????? ?? ?????? ???? ???? ?? ???? ?? ???? ????? ????? ????? ?? ????? ??? ????? ?????? ???? ??? ?? ?? ??????? ?? ?????? ??????? ???? ?? ???? ?????? ?? ??????? ?? ???? ??? ??? ????? ??? ???? ??? ?? ??????? ?? ???? ??? ????? ??? ??? ?? ?????? ???? ???? ?? ?????? ???? <????? ???? ???> ?????? ????? ??? ?”? ?? ???? ?????? ?? ???? ???? ??? ??? ??? ???? ???? ???? ?”? ??? ????? ??? ??? ???????? ??????? ??? ??? ???? ????? ?????? ???? ??? ????? ???? ?? ?”? ??? ???? ??? ?????? ?”? ???? ???? ????? ???? ?????? ?”? ??? ???? ???? ???? [?”? ???? ????] ??? ???? ???? ???? ?? ???? ????? ??? ??? ??? ??? ??? ???? ??????? ??? ???? ????? ???? ????? ????? ??? ???? ????? ????? ?? ???? ????? ????? ?????? ??? ???? ????? ???? ????? ???? ??? ??? ??? ??? ??? ??? ??? ???? ??? ???? ??????? ??’ ???? ?????? ????? ???? ?? ???? ??????? ???? ?????? ???? ??? ?????? ??? ?????? ??? ??????? ?? ??? ????? ???? ????? ????? <????? ??????> {????} ??? ??? ??? ???? ??? ???? ????? ??? ????? ???? ??? ????? ?????? ???? ?? ????? ?? ?’ ???? ??? ?? ??? ???? ??? ?? ??? ??? ???? ???? ????? ???? ???? ????? ????? ????? ???????:
Beruria, the wife of R. Meir, was a daughter of R. Hanina b. Teradion. Said she [to her husband], ‘I am ashamed to have my sister placed in a brothel.’ So he took a tarkab-full of denarii and set out. If, thought he, she has not been subjected to anything wrong, a miracle will be wrought for her, but if she has committed anything wrong, no miracle will happen to her. Disguised as a knight, he came to her and said, ‘Prepare thyself for me.’ She replied, ‘The manner of women is upon me.’ ‘I am prepared to wait,’ he said. ‘But,’ said she, ‘there are here many, many prettier than I am.’ He said to himself, that proves that she has not committed any wrong; she no doubt says thus to every comer. He then went to her warder and said, ‘Hand her over to me. He replied, ‘I am afraid of the government.’ ‘Take the tarkab of dinars.’ said he, ‘one half distribute [as bribe], the other half shall be for thyself.’ ‘And what shall I do when these are exhausted?’ he asked. ‘Then,’ he replied, ‘say, “O God of Meir, answer me!” and thou wilt be saved.’ ‘But,’ said he, ‘who can assure me that that will be the case?’ He replied, ‘You will see now.’ There were there some dogs who bit anyone [who incited them]. He took a stone and threw it at them, and when they were about to bite him he exclaimed, ‘O God of Meir answer me!’ and they let him alone. The warder then handed her over to him. At the end the matter became known to the government, and [the warder] on being brought [for judgment] was taken up to the gallows, when he exclaimed, ‘O God of Meir answer me.’ They took him down and asked him what that meant, and he told them the incident that had happened. They then engraved R. Meir’s likeness on the gates of Rome and proclaimed that anyone seeing a person resembling it should bring him there. One day [some Romans] saw him and ran after him, so he ran away from them and entered a harlot’s house. Others say he happened just then to see food cooked by heathens and he dipped in one finger and then sucked the other. Others again say that Elijah the Prophet appeared to them as a harlot who embraced him. God forbid, said they, were this R. Meir, he would not have acted thus! [and they left him]. He then arose and ran away and came to Babylon. Some say it was because of that incident that he ran to Babylon; others say because of the incident about Beruria.
Thus, we see that calling out to the God of Meir can be effective.
(Above culled from 2 external sources.)