This is the very popular "anim SMOOTH" script found in-world and used for texture animations.

anim_SMOOTH.lsl

// anim SMOOTH Script
// By Doug Linden (I think)
//
// Drop on an object to make it change colors.
//
// If you are interested in scripting, check out
// the Script Help under the help menu.
 
// The double slash means these lines are comments
// and ignored by the computer.
 
// All scripts have a default state, this will be
// the first code executed.
default
{
    // state_entry() is an event handler, it executes
    // whenever a state is entered.
    state_entry()
    {   
        // llSetTextureAnim() is a function that animates a texture on a face.
        llSetTextureAnim(ANIM_ON | SMOOTH | LOOP, ALL_SIDES,1,1,1,1,0.25);
                            // animate the script to scroll across all the faces.
    }
 
 
}