PNG ICO ICNS MORE
Desktop apps
Smooth
Farm-fresh
secure, Lock
DarkGoldenrod
32x32
3D
Hornet
secure
Black
128x128
One bit
Lock, Blue, secure
DarkGray
48x48
Pixel
Diagona Icons
security, password, Lock
16x16
Mac OS X style
Lock, secure, private
512x512
Windows 7 toolbar full
search, secure
256x256
secure, search, config
search, secure, Clock
search, secure, Unlock
KDE Crystal Diamond
File, locked, secure
Snow
Glyph
16x16 Free Toolbar Icons
password, Close, secrecy
unsecured, Access, Broken
PNG MORE
Free Applications Icons
Unlocked, password, Protection
24x24
Protection, secured, private
Lock, clef, private
Key, private, login
Log in, private, password
