A Note on Painting Wooden Weapon Shafts

I've always been a bit beguiled when it comes to painting weapon shafts - you know, spears, flails, etc.  It's easy to do a simple highlight but with that large amount of blank, cylindrical space, I always felt that a wood grain texture gives the model more life.  The problem I've had is finding a way to paint such for a 20+ figure unit in way that looks good and is efficient - the latter of