WoWDB

A Spirit of Harmony is formed from ten Motes of Harmony. Both the motes and the spirit are Bind on Pickup, though they may be made Bind on Account at a later date. (Source) Spirit of Harmony is used both to craft powerful items and to purchase recipes and other goods.

For a brief window of time after Patch 5.1 went live, Spirits of Harmony could be sold to vendors for 250g each. A full stack would net you a cool 5K gold. It was hot-fixed approx. two hours later.

Also, The Daily Blink (a Warcraft-themed web comic) created an amusing comic that well encapsulates players' attitudes about the required component (Mote of Harmony) for the item. "Re-Mote Possibilities"

Quote from Lore »

@rebrown38 @WoWMonk No plans to make those (or Spirits) account-wide.

No longer any point in stockpiling these in the hopes of it being unbound in 6.0. =(

In WoD beta build 18888, the Spirit of Harmony is no longer BoP. Keeping fingers crossed it stays that way! UPDATE: It did! :D