A good Maker is constantly on the lookout for free building materials. This usually means scanning the curbsides as you drive, browsing through the free section of Craigslist, and taking an occasional trip into the land of dumpster diving. When you see that pile of things that you just happen to know house parts that would ordinarily cost you a considerable sum, the elation is unavoidable.

Just because something is free or cheap doesn’t make it worthwhile. However, here are 8 finds that you can nearly always crack open to reveal a goldmine of parts inside.

1. Old computers

Computers are stuffed to the brim with useful parts. They have so many parts and pieces that can be useful in other projects, it’s kind of amazing that people just give them away for free. Here is a list of some of the most common parts you can scrounge from a broken computer on the curb.

Fully working power supplies

Lasers!

Big, fat, pretty heatsinks

Stepper motors from the CD and floppy drives

Matched rack-and-pinion sets from the CD drives

Strong magnets from the hard drives

Project example: Turn a PC power supply into a bench power supply

2. Printers, fax machines, and scanners

There are times when it is literally cheaper to buy a new printer than it is to buy new ink for it. This is incredibly wasteful and results in tons of printers showing up for free on Craigslist or in dumpsters. If you’re doing robotics though, printers and the like are sources for some great parts:

DC motors

Stepper motors

Optical sensors

Smooth rod

Geared motors with matching belts

Project example: Wind Lantern

3. Projection TVs

These hulking dinosaurs are dying out due to the popularity of flat panel TVs. This is good for us Makers as they keep showing up as totally free items, sometimes working but often not. Either way, if you need some optics, these things can be a fantastic source.

Massive fresnel lens

Smaller lenses for the individual projectors, housed within (usually 3)

Project example: Giant Fresnel Solar Heat Ray

4. VCRs

VCRs may be antiquated now, but they’re still available. And they have some pretty cool components:

A hefty and solid rotary encoder (the VCR head)

Linear actuators

Springs

DC motors

A timing circuit

Project example: VCR Cat Feeder

5. Power Wheels

Once the gas pedal stops working on these, they often end up in the dumpster. However, the drive motors and battery are often still perfectly fine. Those powerful motors may not be fast, but they’ve got decent torque for something you got for free.

Project example: Power Racing Series Clown Car

6. Radio controlled toys

Cheap radio controlled toys are everywhere now. This means that as the flimsy plastic bodies give out, the good stuff gets tossed with the rest. You can easily repurpose a cheap R/C to trigger your Arduino.

Project example: Controlling an R/C toy with a USB steering wheel

7. Tires

Tires are a pain to get rid of. You often have to pay to have them hauled off. You can imagine the relief many will feel when a Maker knocks on their door asking if they can take away that pesky pile of old tires. Little do they know, you’re collecting the raw materials to use in some pretty incredible sculpture, or possibly getting new soles for your homemade shoes. Get yourself a standard desktop metal shear and you can cut through them like butter.

Project example: Running shoes with tire soles

8. Old clothes

If the Swap-o-Rama-Rama has taught us anything, it is that there is no such thing as trash fabric. Any fabric is good, and frankly, you can find some really nice material in piles of things being given away for free.

Project example: Make a garden apron from upcycled jeans