Albertus Magnus (1193-1280) - "Albert the Great" was a Dominican monk who was also a reknowned scholar. He wrote many treatises on a wide variety of topics - from astronomy to zoology - and was well known for his encyclopaedic knowledge in these areas. Like so many of his contemporaries he was also a philosopher with views on the nature of science: "Natural science does not consist in ratifying what others have said, but in seeking the causes of phenomena." Also a strong advocate for the co-existence of science and religion, he was made a saint by the Catholic church in 1931, and named the patron saint of scientists (as well as students, medical technicians and, uh, Cincinnati, Ohio) ten years later. St. Albertus also dabbled in alchemy (hey, nobody's perfect) and legend has it that he discovered the philosopher's stone, as well as creating a mechanical automaton (see entry for 'androides') that can answer questions. A saint building androids, turning lead into gold - all sounds pretty cool. In terms of REAL scientific acheivement, in addition to his voluminous writings, Albertus Magnus is also credited with being the first person to isolate the element arsenic.
William of Ockham (1288-1348) - Not quite a scientist, but definitely an early contributer to the philosophy of science, William of Ockham was an English friar of the Franciscan order. He wrote physics commentary but is most widely known for coining Occam's Razor which states "entia non sunt multiplicanda praeter necessitatem" (or, for those who don't read latin, "entities should not be multiplied beyond necessity") While not a scientific law, the idea is often invoked in scientific discussion and forms an integral part in many philosophies on the scientific method including those of Popper and Kuhn. Consciously or not, we all rely on it from time to time in it's form "All things being equal, the simplest solution/hypothesis/explanation tends to be the best one."
Gregor Mendel (1822-1884) - Born Johann Mendel, the 'father of modern genetics' was a member of the Augustinian order of monks. Mendel is a common name in any high school biology classroom because of his ideas about inheritance. He was an avid gardener and spent 7 years of his life cultivating and testing close to 30 000 pea plants, developing ideas about dominant and recessive traits and giving us the classic ratios anybody who has done a Punnett square should be familiar with. His paper "Experiments in Plant Hybridization", describing the work, was roundly criticized (the prevailing idea at the time that pangenes were responsible for inheritance, a view Darwin himself held) and received little attention until well after Mendel's death. His legacy? Mendelian genetics and Mendel's Laws.
Georges Lemaître (1894-1966) - OK, I'm cheating on this one. Lemaître wasn't a monk, but he was a Roman Catholic priest and a member of the Pontifical Academy of Sciences where he was asked by the Pope to investigate the subject of birth control. But birth control wasn't his claim to fame, nor is it why he makes this list. Georges Lemaître is famous for postulating the Big Bang Theory, and formulating an early version of Hubble's Law (before Hubble himself). Hubble's observations suggesting an expanding universe support the Big Bang theory. Though it is a widely accepted explanation of the origins of the universe, the Big Bang isn't without controversy, mostly regarding it's theological implications. At the time of it's publication in Nature in 1931, theists interpreted the Big Bang as a creation event and the religious implications that went along with it. Lemaître, however, was an advocate for the co-existence of science and religion and had this to say on the subject:
Robo-monk (1999-present) - While the above examples are of monks contributing to science, Robo-monk is an example of science (well, engineering really) contributing to monkdom. Made out of recycled parts (from bicycles, washing machines, etc.), Robo-monk spends most of his time in silent meditation. When it detects a worshipper approaching, the praying tin-man rhythmically beats a wooden drum while leading a prayer. The only question is, does it have a soul? Leave it to the Japanese to come up with something like this, but with robot priests maybe I'll convert to Buddhism.
"As far as I can see, such a theory remains entirely outside any metaphysical or religious question. It leaves the materialist free to deny any transcendental Being. He may keep, for the bottom of space-time, the same attitude of mind he has been able to adopt for events occurring in non-singular places in space-time. For the believer, it removes any attempt at familiarity with God, as were Laplace’s chiquenaude or Jean’s finger. It is consonant with the wording of Isaias speaking of the “Hidden God”, hidden even in the beginning of creation."
So there you have it, a small sampling of science that was the product of monks, and one monk who was the product of science. Who says science and religion can't mix?