I would personally go with upgrading my RAM to 8 GB Have a HDD of 350 GB, more than enough for me; and CPU is pretty funky, so don't wanna change it!
Personally I'd have to spend it on beer. I already have 4gb ram, plenty of hdd space and recently upgraded CPU to Q6600.
my RAM is ok, HDD space is still ok, so I'll upgrade my CPU for me to run more processes.. all at once..
I would spend the most on graphics card as I have 4gb ram and 500 gb sata Yeah, but thats not needed, 2x2gb is OK
I'd go with the hardrive, you'll never have too much storage with all the movie and music files out there
Sounds like external hard drives are the way to go to increase capacity. I wonder if a manufacturer will come up with an external CPU? Or external RAM??