Reverse Message Program # Alex Grattan
# 17/10/14

message = input("Enter your message to have it printed backwards:")
split_message = list(message.split())
reverse_message_list = []
reverse_message = ""

for i in range(len(split_message)):
    reverse_message_list.append(split_message.pop())

reverse_message_list = [x + ' ' for x in reverse_message_list]

for i in reverse_message_list:
    reverse_message += i

print (reverse_message)
split returns a list already, so you don't need the list call
unless you really want to reimplement the reverse method, use it, or the function reversed if you want a return value instead
concatenating strings is much easier with " ".join(...)


So this can then be compressed to

# Alex Grattan
# 17/10/14

message = input("Enter your message to have it printed backwards:")
print (" ".join(reversed(message.split())))