About two years ago, I bought a huge blade (19" long and 4 1/2" wide--with a 4" offset bar and a 4" spike to fit into a handle) at a garage sale.  No handle.  I had no idea what it was, but the price was right, and so it went home with me.  And so it lay on a bench for a year before I found that it is an English pattern hay knife. It looks like this one:

http://www.ebay.com/itm/Vintage-Hay-Knife-w-wood-handle-20-Primitive-Barm-Rustic-Decor-/361595433357?hash=item5430c4718d:g:OnwAAOSwP~tW2I8O


Really nice condition with great patina and no rust or pitting at all.
Finally got around to fashioning a 13" oak handle with a 3" ferrule.

http://www.farmcollector.com/tools/feeding-loose-hay-from-an-outside-haystack.aspx

The thing looks absolutely medieval--and the design surely is.  So, what do I do with it now?

Go find some hay to cut and have a blast.

These were made to saw into the hay stacked in a barn.  A pile 15 foot high was really compressed, down at the bottom.  So the hay knife came out to saw an armload to feed the stock.   Today, horse people try to buy the small bales, which feed easily, but end up with the huge round bales.  Seen them try to cut into them with chain saws, (Plug immediately).  Or hedge trimmers, no luck there either.  But 100 year old hay knives, do the job.  There may be horse people around you, but if they buy it, guarantee it won't look nice for long.  Hang it on the wall.

A couple of great suggestions there!