Installing more programs to clear disk space is counterintuitive. For me, most of my drive space is taken with static files - my music collection, all now digitised, weighs in around 60GB (It took up a lot of physical space on CD, too...), and game DVD backups cost around another 100~200 GB all told. (Love double-layer 15GB DVDs for that).
Hard drives are inexpensive now, really. The drives in my machine add up to 2TB, though I only use two of them for actual storage (RAID configuration with data striping for backups, leaves me with about 750 GB of addressable space, of which I hover in around 500GB.
Space micromanagement is therefore not really an issue for me, those days of squeezing megabytes out of tiny storage devices are long gone personally. However, what I find does help is to clean up all the scrap files I download around once a month, as well as temporary files and the like, web browser caches can get pretty large if you stream a lot of video and don't reboot often. Windows' bundled programs handle that fine, personally, and I've never felt the need to add in more programs to my system to manage hard drive space usage.
In conclusion, if you've got a lot of hard drive space, like 1/2 a terabyte (Which in the grand scheme is no longer a lot), 10GB isn't much. If not then of course it is, but you can't keep hard drive space forever - internet connections and a data-heavy policy make it all but impossible without constantly going back over and deleting everything once you're done with it. Thankfully, hard drives are so cheap now it's actually usually more efficient to just get a new one when one gets full.
