I purchased a £5 Natural History Museum microscope for No.1 for her birthday. I was so impressed that I got another for myself. Then I discovered that you can take pictures from it using an iPhone.
Here we see a collection of tiny specs on my desk magnified x40. One I think is tobacco, another a fibre. And yes, the third must surely be a bogey.
There was also this. I was actually using my iPhone 4 camera flash (via a torch app) to light a DVD I was trying to examine. Then I got this awesome shot of the inside of the iPhone flah bulb. Beautiful micro-engineering.
My folks gave me my birthday present a day early. A microscope! Here we see an iPhone 4 retina display. First at 100x, then 300x and finally 600x. Very, very cool.