I've tried several times over the years, but this time I'm going to do it, damnit! I'm going to read at least one book of Newton's Philosophiæ Naturalis Principia Mathematica (aka Mathematical Principles of Natural Philosophy). There are three books in it: The first covers the laws of motion and gravitation, the second covers motion in a resisting medium, and the third is the application of his gravitational theory to the solar system. I will read at least the first book, and probably skim the rest. Because it's Newton, and I'm a physicist, and how can I call myself a physicist if I haven't studied Newton?
Since I suck as a scholar I will read it in English, not Latin. There are many different English editions out there, but most of them (yes, including the so-called Hawking edition) are revisions of an 18th century English translation by Andrew Motte. The Cohen-Whitman translation that I'm reading was done in the 1990's, bringing it fresh from the original Latin to modern English without any intermediary translations, and has extensive commentary by the translators. It's sometimes called the "Big Blue" translation because it is large and blue.