You can also use this syntax (L[start:stop:step]):

mylist = [1,2,3,4,5,6,7,8,9,10]
for i in mylist[::2]:
    print i,
# prints 1 3 5 7 9

for i in mylist[1::2]:
    print i,
# prints 2 4 6 8 10

Where the first digit is the starting index (defaults to beginning of list or 0), 2nd is ending slice index (defaults to end of list), and the third digit is the offset or step.

First and foremost: Python for loops are not really the same thing as a C for loop. They are For Each loops instead. You iterate over the elements of an iterable. range() generates an iterable sequence of integers, letting you emulate the most common C for loop use case.

However, most of the time you do not want to use range(). You would loop over the list itself:

for elem in reversed(some_list):
    # elem is a list value

If you have to have a index, you usually use enumerate() to add it to the loop:

for i, elem in reversed(enumerate(some_list)):
    # elem is a list value, i is it's index in the list

For really 'funky' loops, use while or create your own generator function:

def halved_loop(n):
    while n > 1:
        yield n
        n //= 2

for i in halved_loop(10):
    print i

to print 10, 5, 2. You can extend that to sequences too:

def halved_loop(sequence):
    n = -1
    while True:
        try:
            yield sequence[n]
        except IndexError:
            return
        n *= 2

for elem in halved_loop(['foo', 'bar', 'baz', 'quu', 'spam', 'ham', 'monty', 'python']):
    print elem

which prints:

python
monty
spam
foo