What are some tips on reducing the disk space used by Windows 7?

Does anyone have any tips on reducing the space used by Windows 7? So far I've got:

• Empty Recycle Bin
• Run Disk Cleanup Wizard
• Use 'Programs & Features' control panel to uninstall unneeded components

However even after all that, my Windows directory is taking up 12GB. I found this other question, but that would require me to hack the windows installation disk and then reinstall my OS from scratch, which I'd like to avoid if possible.

Edit: Reason for this question: I already have a spare drive where I store non-essential stuff, but my main C: drive is a small expensive SSD, so the more space I can clear on there, the better. I already run WinDirStat to find stuff in my home folder, and which apps in Program Files are taking up too much space, this question is specifically for reducing the 12 GB in C:\Windows.

Solution 1:

Install and frequently run ccleaner. Defragment your disk (which is probably the biggest). And lastly (if you can), just buy a terabyte external hdd, they are about a 100 bucks and you never have to worry about disk space again :)