I began my decrapification last summer. I've parted with LOTS of things in that time. Some straight-up trash, but quite a bit of it actually of value. Its still a work in progress.
I had a bad habit of buying "collectables" in my 20s. A good chunk of these I've ebay'd away (and made a good bit of money too!). Ebay is your friend for things of value. It may take longer to get them out of the house than putting them in the can by the curb, but someone else gets to love the items you've held onto for FAR too long.
The largest items I've parted with were a 1996 Accord (sold through CraigsList) and a 1998 Honda Shadow (motorcycle). Other items of note: 9 full boxes of paper and magazines (that got recycled into our local newspaper), a complete bedroom set included queen size bed and 3 dressers (I still have the darn headboard though
), a drivers side door to a Honda Accord (dented, gave away to a scrapper), a small bag of computer processors (Pentium Pros have 1 Gram of gold in each!), various comic book collectables (two full sized Green Lantern props) and action figures all went to ebay, A laptop that never lived up to its potential (ebay), 20 or so incandescent light bulbs and light fixtures (given away to habitat for humanity).
If anyone wants to help ME on my quest to decrapify, please bid on the Laserdisc Karaoke player I have up on ebay.
Actually, I am still looking for a way to get rid of automotive plastics. I have an aircleaner box, a couple of plastic body parts, and headlights. If anyone has a suggestion besides the curb I'm all ears!