Some time ago I wished to experiment some photographic tecniques, to create effects that makes you marvel.
Some of these tecniques are actually very simple, as smoke photography, light painting, and also using a flash snoot to make unique photos.
Here I explain you to build a flash grid snoot from daily use objects. My flash is a Canon 580EX but you can make the snoot of this Instructable probably for any flash.

Step 1: The Glittering Extremely Rare Container

This is simply a soap plastic container, the one with dispenser you can find i~~n any shop~~ I don't know where [UPDATE: I'm still searching another one after years]. Maybe you can go to choose your soap taking your flash with you... this should be funny!
You've to cut out the bottom of the container, left the round border so it should keep the straws inside. Also cut the container about 8 cm high. To make a perfectly straight cut you can choose to wrap around the container a paper sheet. Aligning the border of the sheet you'll have the trace for your cut. Use a saw or a cutter and refine the border with some sandpaper.

Step 2: Softening It

Now you have to wrap the head of your flash with some paper packaging tape, so it should protect your flash and also make some thickness which let your snoot fit better on the flash.
When the tape is applied you can heat your plastic container on the flame (any heat generator should be good, also a powerful dryer, beware to your fingers, use a leather glove). Whirl the container keeping only the far end above the heat, so it will become soften without melting. This is a particularly tricky process, so maybe you should buy two soap containers (you'll be also as clean as never with your new flash snoop!).

Step 3: Suit It

When the container has been soften enough (you have to decide yourself when it should be...) you have to try fitting it on the flash (which already has been wrapped with tape). Maybe you have to enlarge the border of the container a little with your finger (this also has to be already wrapped in the glove!) and if the plastic is the same of mine it will be a little elastic so it should tighten up the flash head.

Step 4: Glue the Straws

When you've cut a certain number of black straws at a length about 2 cm less than the plastic snoot (isn't a soap container anymore), you need to arrange them in the shape of the snoot and glue them.

Step 5: Assemble It

The best way could be to put them tight fitting in the noose, and then drip some acrylic glue in the spaces between them. Don't worry if the glue fills the little spaces, because it shouldn't block too much light, anyway blow inside them when the glue is still liquid, to let it reach the bottom.
Another way is to glue the straws one to each other with an ordinary glue, trying to follow the shape of the snoot, and in case remove at the end the straws in excess.
When the straws group fills with a certain strenght inside the snoot, take out it and wrap it with some transparent tape, so it becomes more resistant.

Step 6: Dress Your Flash

Everything is done, you have now to remove the tape from the flash and try if the snoot fits well. If it's a little loose don't worry because if you're lucky the plastic tends to retrieve the original shape, wait a few time to see if something changes. If not you can heat the snoop again (in this way it will surely shrink) and make again the process with packaging tape around the flash, the same you have to do if the snoop is too much tighten (in this case use more tape).
You can now insert the straws inside the snoop. Don't glue them to the snoop to keep the possibility to use it empty. Indeed I'll show you in next Instructable a way to make a 360° flash diffuser with it (UPDATE: here it is Omnidirectional Flash Diffuser).

Step 7: Make an Effective Test

Now you have a beautiful flash grid snoop almost for free. Here you can see how much regular is the round shape, and how much smooth is the light edge. To give you an idea of the angle of the light beam, I've shot this photo with my Canon 40D and 50mm 1.8 lens. If you consider the crop factor of 1.6 you have an 80mm, the best lens for portraits.

Step 8: Done!

Here is an example of a photo taken at a picture, I'll post a portrait soon. Maybe one in daylight, which is in my opinion the best way to take the advantage of the grid snoot.