With the rising cost of postage, gift cards are becoming the most affordable means of shipping a gift to a loved one that lives out of town. Once they are spent, the card is usually thrown away.
There are other plastic cards that are thrown out, too. Yankee Candle Company sends out advertisements that are like a post card, printed on plastic that can be punched into individual coupons. Many grocery stores have member cards that earn a discount on purchases, and from time to time, they issue new cards to replace the older one. Credit cards expire after a few years and should be cut up to avoid identity theft.
All of these plastic cards can be recycled into guitar picks. Use a purchased pick for a pattern. Trace the shape with a very fine tipped permanent marker. Point the shapes one up, one down, to get as many picks as possible from the card, and to reduce the amount of cutting needed.
If the card has raised numbers like those on a credit card, they should be placed on the holding side of the pick. The texture will make it easier to hold the pick while strumming. Do not put the raised numbers on the strumming point because it will make it more difficult to slide the pick over the strings.
Cut the bilateral triangles with heavy duty scissors. Round off the tips of the triangle. To make the edges smoother, buff the edges with a sander, a moto-tool with a sandstone grinder, or a rotary tool used to file fingernails.
Summer camps often use guitars for music in their program. These picks will make a nice supply to keep on hand for those moments when a pick gets lost and needs to be replaced.