I had no intention of buying this, honest (the body; I already had the lens).
The guy I bought my Jupiter 8 from had a IIIg for sale as well, and I've been trying for about six months not to buy it.
You're not helping.
I did drop by a toy store to shop for my daughter and found that they had gone out of business, so in remorse I picked up a Pentax ME from a thrift shop. The last thing I needed was another SLR, but it had a 28/2.8 that will see some love later, and it's just so tiny I thought it would make a good travel camera.
Once I got it home, I found it behaves extremely well with my M42 adapter. None of my M42 cameras have reliable meters (about half don't have one at all), and between the small size and the neglected glass it went from an impulse buy to a camera I'm excited to shoot with.
It currently has a Vivitar 135/2.8 mounted (for some Fukase-style raven hunting), which throws off the balance but still feels good. It also makes me want to start stalking the Mir 37/2.8 again.