From http://www.masonicworld.com/education/, comes the following tidbits:

Hiram, the architect of Solomon’s Temple (One of the most famous of Masons):

An Oriental legend traces the lineage of Hiram from Adam through Tubal Cain and Nimrod, the builder of the Tower of Babel.

On Nimrod being a Mason:

“Every reading Mason is aware that from the time of the original of the “Cooke” MS. Constitutions, say A.D. 1400, it has been handed down that the hunter King, Nimrod, was a Grand Master”

“For some hundreds of years our Constitutions have asserted that Nimrod was a Grand Master and gave the Masons a Charge which we still follow.”

“Our oldest Masonic manuscript (Regius Poem, dated approximately 1390) traces Masonry not to Solomon but to Nimrod and Euclid, in a still earlier time.”

“The oldest known Masonic text, the “Old Charges,” which dates at least as far back as 1400 A.D., sets out a legendary heritage that begins with the antediluvian (pre-flood) patriarch Jabal, who discovered geometry (“the which Science is called Massonrie”) and wrote down his findings on pillars of stone. After Noah’s Flood destroyed all human civilization, the Egyptian sage Hermes Trismegistus rediscovered this knowledge and passed it on in a lineage that includes Nimrod.”

From Manly P. Hall’s “The Secret Teachings of All Ages“:

“The rakshasas or men-demons of Lanka, the opponents conquered by Rama in the Ramayana, are some of the latest representatives of the Atlanteans in their last days. These rakshasas correspond to the Greek titans, the Egyptian colossal heroes, the Chaldean izdubars, the Jewish ‘eimim (terrifiers) of the land of Moab, and with the famous giants anakim (`anaqim) mentioned in Numbers 13:33. According to Manly P. Hall, Izudbar was Nimrod, thus he was a giant, or Nephilim (anakim), a descendent of the Fallen Angels.”

“…In his Chaldean Account of the Genesis, George Smith, copying from the cuneiform cylinders, in describing the wanderings of the hero Izdubar (Nimrod)…”

From “The Encyclopedia of Freemasonry and it’s kindred Sciences“:

“The legend of the Craft in the Old Constitutiom refere to Nimrod as one of

the founders of Masonry, Thus in the York MS. No. 1, we read : At ye making of ye toure (tower) of Babell there was Masonrie first much esteemed of, and the King of Babilon was called Nimrod, a Mason hmself, and loved well Masons.”

And the Cooke MS. thus repeats the story: “And this same Nembroth (Nimrod) began the towre of babilon and he taught to his werkemen the craft of Masonrie, and he had with him many Masons more than forty thousand. And he loved and cherished them well”

“…The Lenadowne Manuscript, whose date is about 1660, it is said that Nimrod gave a charge to the Masons that “they should ordaine the most wise and cunning man to be ‘Master of the King’“…