Off topic....did you know dull sewing machine needles are great as hangers for pics on wall...not heavy things..just light things...even a wallhanging.....seasonal stuff . The leave almost no hole. I will save a few at a time....and have used to "hang things"....better than those 3M things that decide to let go in the middle of the nite and scare the beejeesees out of you!

I throw away just about all of the stuff already mentioned plus tons of tear away stabilizer from the back of my applique. Time is the most troublesome because it is often "wasted" due to procrastination. I actually went back to work because I get more done when I have to manage my time better and I love the interaction with other quilters!

Used sewing machine needle, scrap batting.

Totally agree about wasting time. So easy to do and u never get it back.

fabric I had for 25 years and I know I will never use (well maybe I donate it unless it is really useless)

Actually I learned something! Had no idea you could use old sewing machine needles to hang wall hangings or other small items. What a great idea! Curses! Now you've given me something else to COLLECT!!!

Dull pins though I've been known to sharpen a sewing machine needle. Icky fabrics become the foundation to string or crazy quilt blocks. Anything smaller than 1.5 wide unless I happen to be piecing minatures. Tiny pieces of batting but never strings of batting. I don't buy much anymore so everything I keep fits in 33 9x13inch baskets. Unless I'm working on scraps, then its everywhere. Good question.

Receipts! I don't want anyone knowing how much I'm spending.
All else can be used or recycled, even down to the lint and tiny threads that's cleaned out of the machines are used by the birds to make nests.

thread ends, small scraps,dull or bent pin's, empty thread spools.

pins in a soap tin -old fashioned I know but it works. As you take the pins from the fabric, stick them into the soap. Works great.
I donate or get rid of scraps, fabric I bought and now look at and say WTH!! was I thinking. Bent pins, broken old needles, dull blades, thread strings, old mags-would love to donate but don't have a guild local-plastic that fabric comes wrapped in-save the bags to keep fabric I make into kits together-things that no longer work or are broken and need replacement-the 'must have' that ended up a 'why in the world did I fall for that?'-empty spools.