Leftover Supplies

What do you do with your leftover supplies?
Use, Donate, trash?
Food Ingredients
Recently I purchased ingredients to make two desserts.  I also purchased a couple extra items in case I made a second one  either because the first was so good or because I thought I might do a trial run.
End result: what do you do with the extra ingredients?  In the past I found a web site that you type in ingredients that you want to use and it will produce recipes that use those ingredients.  Also you could ask people that are local if they would like the extra ingredients to use.  Third, if you are not planning on using the item before the expiration date you might as well toss the ingredient and keep the room in the cabinet or the refrigerator.
If you know ahead of time that you are going to have extra of an item such as buttermilk, sour cream, cream cheese, plain yogurt or other perishable things maybe you can find another recipe that will use the excess ingredients.  Your family may enjoy the unexpected cheese cake.  Can the item be repackaged and frozen for later use?
Craft Items
I recently bought iron on letters to use on a shirt.  I only used 7 of the letters.  What should happen to the rest of the iron on letters?  Can it be used for another project?  Can you give it to someone else?  Should you toss it?
The Excess
We should consider what to do with the excess when we buy the item.  We might buy a smaller amount or buy something different that we can reuse or buy something different where there is nothing left over.  How many of us have a few plates from a party or a piece of wrapping paper from whatever gift giving occasion?  I once had a pollyanna type party where I wrapped all the gifts in different left over pieces of paper.  An idea for the extra plates is to use at another party even though the theme is not correct or save them for vacation so you have less dishes to do when you eat in.  When buying the plates you could buy less of the themed plates and include more generic plates so that you can definitely use the extra plates at another event. 
It is good to save things but only if we seriously plan to use the items in the future.