Are you talking about all kinds of ( stuff) or just sewing/ quilting stuff?
FAcebook has ( buy sell & trade ) pages for local listings. You can donate items that don't sell to habitat for humanity stores, goodwill, Salvation Army-- many different places. Sewing/ quilting items can go to local senior centers, care facilities with activity departments, area guilds... We have ( selling/ listing, donation) pages here on the board....just depends on what ( stuff) you are trying to unload

can you be more specific about the items?

I was wondering this as well

I donate what I don't sell to our local Humane Society thrift store, I'm sure there are lots of good organizations that would be thrilled to receive your donations.

Donate what doesn't sell. It doesn't do you any good to have items that are you are not using and bug you. Maybe quilting groups at your local churches or sewing guilds. We have a recycling group that donates to non profits so I always donate to them for distribution. There are also fundraisers for charities that will sell your items (like rummage sales for the animal shelter). It can be painful because you know these things will be sold for pennies but unless you want to take on the challenge of selling on ebay or craigs list or multiple yard sales, it is a workable solution.

Life is short.

We get fabrics and book donations at the Local senior center. Many places will take what you don't sell.

Box up everything you don't want and donate it anywhere that take donations. Easy.

call some of the thrift stores near you and ask if they will accept it. also put it free on craigslist.

Give Away fabric
 

I just clean out my stash and give it to Senior Citizens group. They in turn make all kinds of things with the fabric.

I just gave away my entire sewing room, including my fleece wall and my peg board storage wall and 1/2 of my fabric stash to a lady at church who had nothing except a gifted sewing machine. She was over the moon and I was thrilled to part with it.