Several years ago I bought a kind of very simple wardrobe from IKEA. It's called Bardu and is made out of steel rods and a plastic covering. It stands on wheels.
There are small plastic piece that connects the plastic rods with the wheels. And one of them broke a while back. I went to IKEA and asked for a replacement part. They told me that they don't ship parts for such old items - but they have an offering quite similar to the Bardu that I could buy. Sadly, the design has changed and the wheels are directly connected, so no compatible replacement part. The E-Mail service from IKEA told me the same: No replacement parts for old products.
At this point I could've complained about the fact that we live in a crazy world where someone suggests to you buying a new piece of furniture because a small plastic part of the old one is broken.
I posted a message in the RepRap-forum asking for help. If you don't know the RepRap: It's a 3D-printer, creating objects based on computer models out of simple plastic. The RepRap is an Open Source project built partly out of parts printed on other 3D printers. The idea is: Everyone can (with enough time and passion) built his own RepRap, all the documentation is available online.
I quickly got a response from someone from France who was willing to give it a try and re-create the needed plastic part on his 3D printer. Some message exchange later I sent him the broken and a non-broken part. Today, I got my RepRap-printed replacement part. It fits in perfectly. I'm seriously impressed.
Update (2012/12/11): I don't want to hide the fact that the whole issue turned out to be much trickier than thought. The original piece broke after a while. DeuxVis was so nice to experiment with likely more stable designs and sent me some more printed parts, but the first one already broke again. You can read the details in the RepRap-forum.
I have a magnet plate hanging over my desk. Usually, the normal magnets for that purpose you can buy in shops are of very low quality and not very strong and fail to hold more than a few pieces of paper.
I recently discovered a way to get much better magnets almost for free: From old harddisks. To open a harddisks, you will usually need some kind of Torx screwdriver. Inside, you will find one or two very strong neodym magnets, which were originally used to move the read head.