[Geej]

Access Internet data safely by dropping unnecessary administrative privileges when accessing the Internet.

DropMyRights by Michael Howard
Read more at MSDN site
Another article for observation on various mode of privilege

Silent Switchless Exe (SaferFireFoxSI.exe)
Size: 316kb
MD5: CECE3073E7EF7F117C98F78776E65713
Installed Directory: Program files\Mozilla Firefox
Additional shortcut: Start->All Programs ->Mozilla Firefox -> Safer Firefox

SaferFireFoxSI.exe

SaferFireFoxSI.exe contains 2 files:
1) DropMyRights.exe
2) SaferFirefox.exe <-- -- -- Launcher using Autoit compiled script. File not UPXed.
So can change your fav icon if you want.
A simple msg will popup if the 2 files are not found at its intended location.
SaferFirefox.exe is set to run in Constrained mode

It is intended to add to your existing Firefox svcpack.

1)Pls unpack your existing Firefox addon program

2)Put the downloaded SaferFireFoxSI.exe into the svcpack folder

3) Edit your entries_Firefox_or_something.ini with

[AddProgram]
Firefox-2016.exe <-- This is my existing entry. You may have different names.
SaferFireFoxSI.exe  <--- Add [b]New entry[/b] (Must be after Firefox-2016.exe line, not before)

4) Repack back the whole package into original form

Other: If you have Firefox already installed, just run SaferFireFoxSI.exe to install.

Q. How do you know that Firefox is running in reduced privilege?
A: Well, Start SaferFirefox thru the start Menu. Try saving this webpage in C:\ or C:\Program Files or C:\Windows or C:\Windows\System32
If you get a warning message, asking you to save to My Documents instead, then Firefox is running in reduced privilege. (which also means spyware can't infect your critical system directory)
Note: It will also block registry writing to HKLM if any (but not HKCU).
However, if you are installing Firefox extensions, then don't run in Reduced privilege.

(Note: DropMyRights does not works on Vista)