http://www.python.org/doc/2.6/glossary.html

The decorator entry in the Python 2.6 documentation incorrectly
describes a decorator as "merely syntactic sugar". It is not, as this
example shows:

>>> def decorator(f):
	f.prev = globals()[f.__name__]
	return f

>>> func = 0
>>> def func():
	pass

>>> func = decorator(func)
>>> func.prev
<function func at 0x00C748F0>
>>> func = 0
>>> @decorator
def func():
	pass

>>> func.prev
0

This distinction could be useful in building multi-methods, for example.