There are times when I wonder how much 'free space' is required in the C: Drive? For instance if you run a cleaner application like say 'Cyber Scrub' it seems to 'take up' all the slack while doing its thing. I notice similar with some virus scanners. The PC at times can become very lethargic when some beast is running around inside it doing whatever it is 'this or that' program does. So... How much 'free space' or 'elbow room' do you have left over in your C: drive? And it would be nice if you could leave a comment as to whether you think 'free space' in C: is important or is 5gb spare the same as 20Gb spare the same as 40gb spare?