Oh, this is rich.  I so -wish- I were the perpetrator of such a wonderful prank... but I wouldn't know how to make an arm out of packing tape if my life depended on it.  Darn!  Found this on Today At Brown:

"The bronze statue of Caesar Augustus near the Refectory on Wriston Quadrangle has maintained its dignified pose and patina through decades of armlessness and pigeon droppings. Recently, however, Caesar was spotted extending a new, shiny right arm made of what appears to be packing tape.

How did the lucent limb get there? And why is it making a gang sign with its hand? No one is sure.

'[The arm] was not something done under the aegis of the curator or Brown’s Public Art Committee,' says University curator Robert Emlen. He added, 'I think it's an interesting idea.'

"The statue was given to Brown in 1906 by Moses Brown Ives Goddard, class of 1854. It is an exact replica of the Augustus of Prima Porta, a c. 15 C.E. marble statue now displayed in the Vatican Museums.

"Originally situated in front of Rhode Island Hall on the College Green, Brown’s copy of the Caesar Augustus statue lost its right arm during the Hurricane of 1938. Mended, it was moved to its current perch in 1952 but at some point thereafter lost the arm for good – until this week."