I have had this handheld USB digital microscope for a couple of months and have found it really handy for working with anything with small geometries, or whenever I want to see something really small. The optical magnification range is 1x to 80x, but is advertised as having even higher magnification through digital zoom (basically, just zooming in on the digital image).
The bang-for-buck is huge even if you don’t need to look at high-resolution negatives from some spy-plane. It can be used at a broad range of magnifications, from microscopic (the fibers in paper look like a log-jam) to its alternate use as a webcam by just changing the distance and re-focusing. It really shines when you put it against something you need a close look at because of its built in light source, two magnification levels set by spinning the focus ring, and the Windows-only software that lets you do calibrated on-screen measurements and side-by-side comparisons with one side live.
The price is low enough you might suspect it’s a toy instead of a tool, but it’s serious hardware. It has a 2 mega-pixel sensor, with decent optics and enough configurable image control to satisfy the geekiest tool buff, but the defaults make it simple and practical to use right out of the box.
There are other USB microscopes out there, but this one is affordable and has so much utility that it’s fun to use. Last time I loaned it out it took weeks to get back because everyone who tried it had to show someone else the snazzy little tool they’d just ordered for themselves.