Soft focus photography can produce some beautiful images when used properly. It's used a lot in beauty and glamour shots, but can be applied to other types of photos as well. Some digital cameras have pre-programmed settings for soft focus shots, but if you're using a DSLR, you'll need a special lens or filter to do it.
Sure, you can always buy one, but with just a sink strainer and a cheap UV protector filter, you can make your own for next to nothing. Here's a quick tutorial by Nick Cool over on DIY Photography.
First, remove the glass from the filter and put the filter frame over the sink strainer. Use a drill bit to make the center hole in the strainer a bit larger (6 to 10mm), then do the same for the rest of the holes using smaller bits.
Once you have the holes the way you want them, cut the strainer to fit the filter frame. To make it look more professional, paint it black before mounting.
Here's some example shots of this DIY soft focus filter in action.
You can find the original instructions, as well as more photos, over on Nick Cool's Flickr.
And if you're keen on repurposing plumbing parts for your digital camera, may we interest you in a DIY tilt lens using a shower head?