What are the halachic differences between left-handed people and right-handed people?
For example, Tefilin are put on right arm for lefties and left arm for righties.
Can someone provide a comprehensive list of the common differences?
R' Paysach Krohn wrote an English-language book on halachos for lefties. It's available free by mail if you call his home; he lives in Queens, New York, and is listed. (Obviously, you might want to pay him for it, and the postage.) It's also online. (Thanks to Dr. Melech Tanen for linking to it.)
The book is arranged in sections, one of which is a list of things lefties do the same as righties, and another of which is things lefties do the opposite from the way righties do; so one whole section of that book answers your question. It contains fourteen subsections:
But consult your own rabbi for practical rulings.