But I only keep the oddly/unusual shaped ones.....and others not so odd or unusual!
Me, too. But like kitchenelf, I mostly save the oddly/unusual shaped ones. I also save vanilla bottles because I make my own vanilla and like to give it as gifts at Christmastime. I also like to save unusual or particularly beautiful wine bottles. I have a wine rack in my kitchen that, instead of wine, has nothing but bottles of different vinegar. We use lots of vinegar - lots of different kinds - here and I needed the cupboard space for other things. Our kitchen is very low on space and one step above a campfire when it comes to being the least bit modern. I also like to save the quaint mustard jars and use them to put homemade mustards or preserves for gift baskets.