If you love Celtic art or knots then take a look at this wonderful website:
J.D Lenzen, the blog owner, is a knot expert and has a wonderful Youtube channel here called 'Tying it All Together"-in case you would like to try your hand at a few knots. Some of the knots are actually surprisngly simple but still look very effective. Others are fairly complex but I think could be mastered with a little practice and dexterity. An honoury member of the International Guild of Knot Tyers (yes, such a thing exists) he also has a book called Decorative Fusion Knots.
I think the knots are incredibly beautiful and could be utilised in many things-jewellery, furnishings, clothes and so on. I'll certainly be investing in some nice cord to try out a few of the Celtic knots.