A quick-and-relatively-easy diffuser for a pop-up flash. I was getting tired of using an old translucent film canister, so I came up with this. I've seen someone selling a diffuser which fixes on the hotshoe but I believe it's constructed in a different way.
It's made out of a plastic ring binder. The one I used cost $2.20 but it will make about 8 of these diffuser. It could even be cut out of an existing binder which could still be used afterwards :-)
This won't work with cameras where the built-in flash is deactivated by the presence of something in the hot shoe. The Canon G7 behaves in this way, for example.
[Edit] The diffusion will only be noticeable at reasonably short distances, given that the effective size of the light source still isn't so large.
Step 1: Find Suitable Material
I used an A4 binder made of translucent plastic. Other reasonably stiff, easily workable and flexible material would also do.
Step 2: Cut Out the Required Shape
This very much depends on the flash head that it is supposed to fix. The "tail" end of the diffuser is the most critical. It needs to slide into the flash head and still have enough friction to stay in place. It should also extend about 1cm (1/2") behind the hotshoe so that the other end has something to fix on to.
Step 3: Attach to Camera
Fit the tail from the front of the camera, through the hole in the pop-up flash and into the hot shoe.
Take the other end of the diffuser (the end with the two slots), pull it over the top of the pop-up flash and feed the end of the tail through the two slots.