Note: Everything that follows is performed at your own risk.
If, like me and may others, you installed Windows 7 Service Pack 1 over Windows 7 vanilla, you probably have quite a bit of wasted space on your primary drive (around 1GB). This is obviously not desirable if you have a relatively small SSD as your primary OS drive.
Given that it is extremely unlikely that anyone would ever remove Service Pack 1 and go back to vanilla, you can quite easily reclaim this space (Note: you will no longer be able to uninstall Windows 7 Service Pack 1):
- Open an elevated command prompt (i.e. Run as administrator).
- Run this command: dism /online /cleanup-image /spsuperceded /hidesp