I did some reseach for you and have found a legitimate Jewish site with the information you need and a picture of the Reb!
It can be found here: http://parsha.blogspot.com/2007/10/mouser-rebbe.html
Questions like this are so interesting, keeps Yahoo Answers intriguing!
LOL! What at first seems like a funny question is true.
"Grand Rabbi Yeshaya Steiner of Kerestir, was the founder of the Kerestirer Hasidic dynasty. He was born on Iyar 3, 1851 in the town of Zbarav, Hungary. When he was 3 years old, his father died. At the age of 12, his mother sent him to study with to Rabbi Tzvi Hirsh of Liska, Hungary, the author of Ach Pri Tevua. When he died and his son-in-law Rabbi Chaim Friedlander author of Tal Chaim succeeded him, Yeshaya started travelling to Rabbi Chaim Halberstam of Sanz. After the passing of Rabbi Chaim of Sanz, he became a disciple of Rabbi Mordechai of Nadvorna. The Nadvorner Rebbe suggested that he move to the town of Kerestir, in Hungary, In Kerestir he became a famous Hasidic Rebbe and became known as a miracle worker. In 1925 he was succeeded by his son Avraham. His image is used as an amulet by Jews who believe that it wards away mice and offers protection against misfortune."
Find rest of story here:
Well, I assume Reb Yeshayaleh Steiner of Kerestirer is a cat.
The Famous Mouse Story-
Affectionately known as Reb Shaya' le ( Rabbi Yeshaya Steiner of Kerestir) , the Kerestirer Rebbe lived around the beginning of the 20th Century. He was a very pious man and extremely humble, always referring to himself in the diminutive ( Shaya' le) . He was known as a "miraculous" person. His greatest pleasure was to host a very elaborate Melave Malka, the meal that follows Shabbos, on Saturday night. Often he would have his chassidim shecht fresh chickens for his meal.
One motzo' ay Shabbos, while Reb Shaya' le was eating this special melave malka meal, a chossid came to him with an urgent request. He was a man who had a warehouse full of foodstuffs and he made his living by buying an selling food. For the past number of months, his warehouse had been taken over by mice who were eating his grain and other commodities and his entire livelihood was threatened. He asked Reb Shaya' le for a blessing that the mice should leave his warehouse. At that time, each small town in Europe was ruled by the local church pastor. Some of the pastors were kind towards the Jews and others were very harsh. Reb Shaya' le asked the chossid if the pastor of the town he lived in was kind or harsh. The chossid replied that he was very harsh toward the Jews. Reb Shaya' le then instructed the chossid to go to his warehouse and to tell the mice, "Reb Shaya' le says to go to the estate of the pastor." The chossid followed the Rebbe' s advice and instantly hundreds of mice raced out of the warehouse all heading in the direction of the pastor' s estate. The chossid' s business was saved and ever since Jews who have been plagued with this problem have used Reb Shaya' le' s picture to accomplish the ridding of mice from their homes