As several others have already noted the K10D was the camera which finally moved me out of the age of film into the digital world. It is pretty dated by today's standards but there is just something about the images this camera generates. I do a fair bit of birding and let's be honest ISO just isn't a strong suit for this camera. I find anything beyond ISO 400 pretty much unacceptable with the K10. As birds like to hide in the shadows poor ISO performance doesn't exactly recommend this camera to birders. That being said if the guys will sit still you can still manage a good shot with the K10. In the image below I used another old timer, a SMC Pentax M 400/5.6, to capture this Common House Sparrow. This fellow was all puffed up trying to stay warm on a very cold day as I recall. My K5 is technically better in every way than the K10 but in many cases I often prefer the look of the K10 results. Go figure.
Another favourite with the K10/M 400/5.6 combination is this Black Capped Chickadee.
I'll often pull it out for portrait work as well. Long live the K10.
Tom G