An bed made from iron pipe. The design is simple yet sturdy. Not too pricy, simple to make, easy to adjust/disassemble, this bed will give your room an industrial feel.

Step 1: Acquire Materials

Here are the required materials

1 1/2" schedule 40 iron pipe: Available at plumbing/hardware stores. Rather heavy. You can buy 10' lengths and then cut it yourself. Note that 1 1/2" pipe is not actually 1 1/2" in diameter. Its really closer to 1 7/8"!
Hacksaw/pipecutter/chopsaw: For cutting the pipe down
Couplers: You can buy these from mcmaster carr, they are used to build railings. They are sometimes called "speed rail" or "speedrail". Search the online mcmaster.com for "speedrail" and order the couplers you want. I got mine for free and they were all of the "4 outlet crossover" kind so I used only those but theres more suitable configurations.
Allen wrench: for opening & closing the couplers
Plastic pipe-end covers: get these at the place with the pipe, they protect your floor
1x8 wood panels for making the slats, and 2x4's for holding the slats together

Step 2: Prep

Measure your matress and couplers to determine how long your pipe pieces have to be.
For my queensize matress and couplers i needed:

4 x 57" for the head and tail of the bed, including the headboard and tailboard
4 x 42" for the 4 legs
2 x 87" for the lengthwise pieces

Cut and deburr your pipe.

Step 3: Headboard

Slide the couplers on the pipe, and make up your headboard, it doesnt have to be in its finished shape but having a square will make it easier to assemble the whole thing. Use the allen wrench to tighten down the couplers

Step 4: Tailboard

Do the same for the tailboard

Step 5: Frame Assembly

Have a friend or two help you hold up the head/tailboards while you slide the lengthwise pieces in. Now you should square the design, make sure it's level, and get it into a final configuration.

Step 6: Slats

Use the 1x8 wood to make slats that will form the support for your mattress. use three 2x4 pieces to hold the slats together, use woodscrews to hold the whole thing together