Tested copy(), [:], and list():

  >>> t1 = timeit.Timer('copy.copy(orig)','import copy;import random;orig = [random.randint(0,255) for r in xrange(100000)];')
  >>> t2 = timeit.Timer('orig[:]','import copy;import random;orig = [random.randint(0,255) for r in xrange(100000)];')
  >>> t3 = timeit.Timer('list(orig)','import copy;import random;orig = [random.randint(0,255) for r in xrange(100000)];')

  >>> print t1.timeit(10000)/10000
  0.00036607401371
  >>> print t2.timeit(10000)/10000
  0.000416543197632
  >>> print t3.timeit(10000)/10000
  0.000372415995598

Probably not the world's most ideal testing here. I have no idea if/how Python caches, for instance. But slice notation continually comes out the slowest in this crummy example.