A really good digital microscope can cost hundreds of dollars. I cheaped out and bought a
$39 model at Amazon.
The reason I picked that one is that it was inexpensive and it has Mac software. I have Windows XP and Windows 8 installed in Parallels Desktop on my Mac, but I'd rather not have to run those if I don't have to.
Setup was easy enough: plug it into a USB port, install the software and I was able to take this:
That's 20X magnification. I had to get the picture using Skitch (a Mac screen capture tool) because neither the red photo button on the camera nor the software photo button worked. That's fine; I'd rather use Skitch anyway.
You adjust magnification using a rather stiff thumbwheel. Supposedly you can get anywhere from 20x to 800x, but Amazon reviewers say it really is only 100x maximum.
I could not get focus anywhere but at the bottom or the top of that range. This is what I got at the high end. Whether that is 100x or 800x or something in between, it is more than enough for my needs.
The microscope includes LED lights that turn on by a switch on the unit. The instructions warn you not to turn on the lights unless their software is already running - they don't explain what might happen if you are careless, but they do mention "electronic damage".
I'm happy with this purchase, though I'd prefer something easier to focus.