Still, it does cost. When I was growing up, we had five-and-dime stores like Woolworth's, Kresge's, and others. They have been replaced by the current crop of dollar-and-less stores. They are great sources of "stuff" for crafters.
Some have skeins of yarn. Lately, I've been having a great time picking up plastic or cloth/canvas tote bags for every project I've got going. Little canvas garden caddies with pockets on the outside are great for WIPs, too.
Small scissors to keep with each project are some of my faves. Little tablets to make notes on adjustments or about the special sizes for special people, are things I pick up, too. I always pick up batteries for my digital camera, to take photos of my finished projects. Some stores have ribbon or foam shapes, for trim. Many have small craft spots; even if it's meant for scrapbookers, there are little stick-on's, beads for trims, fake fur yarn, glue, and more. Then there are labels for my totes, small organizer container sets, and more.
Oh, I guess you can tell I'm having a love affair with my local 99-cent store! I confess, I'm helpless in its clutches.