PNG ICO ICNS MORE
UI
Pixel
Fugue Icons
Check, ok, Accept
RoyalBlue
16x16
Gnome icons
drag, Folder, Accept
DimGray
32x32
Accept, Calc
Black
24x24
Accept, Circle, tick
Green
Tango
Accept, drag, Folder
DarkGray
Mini
yes, positive, green
YellowGreen
Accept
DarkSeaGreen