The Windows 7 Lite edition is much smaller than the Windows 7 Full edition. Even the Installation disc itself is almost half of the size of the normal Windows 7 setup disc.
Normally, the Windows 7 OS would take up about 10 GB of space when you have finished installing it. The Windows 7 Lite edition only takes up 2 to 6 GB after you have finished installing it. That is enough space for you to install Windows 7 Lite on a 8 GB compact flash hard drive. The only thing about Windows Lite is that some of the features that are new in Windows 7 will be removed. You may not have the speech engine which allows you to control your computer with your voice. On the other hand, you will have the Windows 7 Aero glass theme and all of the basic things of Windows 7. Of course, you will also have the new core parts that are unique to Windows 7 when you install Windows 7 Lite.