This is basically a just a homemade water pump made from some things you might have around the house. Its useful for many things. This isn't my idea, so give credit to junits15.

What you need:

water bottle with cap
aluminum can or other metals you can cut
motor (one that spins fast?)
tubing (copper or other source...)
wire
plexiglas
power source (3 - 9 volts)

Tools:

hot glue gun
scissors
hacksaw
drill

Step 1: Prepare the Bottle Cap

We only need the neck of the bottle. Cut the bottle near the top and sand it down.

Drill a hole in the middle of the bottle cap making sure its centered about the same size of the middle of the motor so it fits in. Drill a hole in the side big enough for the tubing going out. Don't forget to drill a hole in the bottle cap so the tubing can flow out.

Step 2: Motor and Impeller

To make the impeller cut a strip of medal about 2 1/2 in. The height of your strip should be a little lower than height of your bottle cap/neck. Then fold your piece of metal in halve, then bend it at a 90 degrees angle where your motor is going to be. Bend all the sides until you have a plus sign.

Hot Glue your motor onto the bottle cap and make sure it spins by hooking it up to a power supply. (It doesn't need to be water proof...) If you haven't screwed the neck off yet do so now. (It'll make things a lot easier.) Hot glue your impeller to your motors shaft and let it cool. Screw your bottles neck back on and your done with this step..

Step 3: Plexiglas and Power

Cut some Plexiglas in a square shape, or any other shape... Square is just easier, and drill a hole in it to fit the intake tube in place. Glue the piece of Plexiglas to the top of your pump and glue the input tube to it making sure it doesn't interfere with the impeller.

Glue the output tube to the side making sure that doesn't interfere with the impeller and you're done....

Connect to a 3 - 9 volt power supply and submerge it underwater and watch it flow!

Step 4: Final Thoughts...

This pump cant pump that high but it still works. If you have a fast motor you can get better results.
I have a slow motor from a ps2 controller and lets say it doesn't work too well...
Also just to tell you all, this only works under water. so make a long cord attaching to the battery, and don't leave it in the water too long or it will rust and not work anymore..

Questions you may ask.

Q. It doesn't work!
A. is the motor working? impeller stuck?

Q. It doesn't go as high as i thought.
A. are you under powering it? try 6v or 9v..

Q. why would i need this?
A. you can use it to pump water for computer water cooling or anything you want.