Data memory usage - Reusing list elements takes only 4 bytes per element.

reuse-of-data-elements.lsl

list facial_anim_list =
    [ "express_afraid_emote"
    , "express_anger_emote"
    , "express_laugh_emote"
    , "express_bored_emote"
    , "express_cry_emote"
    , "express_embarrassed_emote"
    , "express_sad_emote"
    , "express_toothsmile"
    , "express_smile"
    , "express_surprise_emote"
    , "express_worry_emote"
    , "express_repulsed_emote"
    , "express_shrug_emote"
    , "express_wink_emote"
    , "express_disdain"
    , "express_frown"
    , "express_kiss"
    , "express_open_mouth"
    , "express_tongue_out"
    ];

list L;

default
{
    touch_start(integer n)
    {
        llOwnerSay("L[9999]=" + llList2String(L, 9999));
        llOwnerSay((string)llGetUsedMemory());

        L = [];
        integer i;
        integer len = llGetListLength(facial_anim_list);
        for (; i < 10000; ++i)
        {
            integer rnd = (integer)llFrand(len);
            L += llList2List(facial_anim_list, rnd, rnd);
        }
        llOwnerSay("Ready for next touch");
    }
}

// On first touch:
// [04:21:40] Object: L[9999]=
// [04:21:40] Object: 6572
// [04:23:42] Object: Ready for next touch
// On subsequent touches:
// [04:23:42] Object: L[9999]=express_open_mouth
// [04:23:42] Object: 46636
// [04:25:45] Object: Ready for next touch