The Leica M9 was the first full frame digital rangefinder. At the time of its release it was also the smallest full frame digital camera on the market. In fact, it wasn’t until Sony released the A7 series cameras some years later that any other manufacturer came close to building a camera as small with a 24x36mm sensor. To this day, the M9 still has a strong user base and even has a bit of a cult following of people who largely seem to appreciate it for the CCD type sensor that sits at its core.
I didn’t buy mine specifically because it’s small (it was the biggest Leica I owned at the time), or because of the CCD, I bought it because it’s the cheapest full frame digital rangefinder on the used market, and after shooting an Leica M8 for a few months it became very clear to me that ‘full frame’, ‘digital’ and ‘rangefinder’ were four words I really wanted to be able to use when describing a single camera in my collection. What I don’t think I entirely expected was just how much I could get out of a digital camera outside of work.