saving weight of my bike

Question
I'm spending some money trying to save grams to my old bike (stumpjumper 2001)

can you tell me, what are the heaviest parts do I must start to change ? (the fork, rims, etc.)

Or, normally what are the parts I have to change first, to achieve less weight faster?. Forget brands and models.

Answer
Hey whats going on? Well, if I were you I would start with handlebars, stems seats and seat posts. See how many grams you can take off there then move on to bigger things. When I say bigger things  mean like wheel sets and forks. After all is done I would start looking at derailrs and techinal stuff. Also don't buy anythign that will compromise the weight of another part. Msure it all works out. Okay, I hope I helped you. Bye.