I'm a newbie and thought the best way to introduce myself would be to share some useful pieces of information regarding the K100D, which will probably apply to some extent to other models as well.
As you know the K100D offers two ways of releasing the shutter (wireless and cable switch (CS-205)) and both accessories are not exactly cheap, at least not here in New Zealand.
Regarding the wireless remote, note that Pentax uses the same infrared code as some SONY remote controls. I have successfully released the shutter on my K100D with my SONY remote control (the exact button will vary between different models of remote controls). It also works with a generic (universal) remote, if it is set to use the correct codes. I was surprised to see that using a remote control this way even supports arbitrarily long exposures in "bulb mode"; as long as you keep the button on the remote pressed, the shutter stays open.
Regarding the cable switch, note that the little plug is a standard 2.5mm one that is often found on mobile phone earphones. If you get such a cable, building the switch yourself is quite easy; here's a link http://www.geocities.com/a_ov_c/cablef.htm
The second option for the cable switch is to buy a cheaper replacement. I found the Yongnuo RS-C1 and it works nicely, but there are other replacement switches as well.
Yes, I would prefer to have "Pentax" written on my remote controls and also wouldn't mind to support Pentax by forking out some money for the original switch, but here in New Zealand the remote controls are prohibitively expensive.
Just a reminder, as you have probably know this at one stage: If you apply exposure correction (something I do quite often), the automatic ISO setting is disabled and ISO 200 is chosen. If that's not what you want, you need to set the ISO speed manually.
You may not be aware of the fact that ISO 400 has a bit more headroom in the highlights then ISO 200, so when choosing ISO 200 you are giving a away a bit of the potential dynamic range. Since the noise at ISO 400 is very well controlled, it appears to make sense to set the camera to this speed and avoid ISO 200 unless you are after minimal noise, but I hope someone else will shed more light on this matter.
Its in the manual, but here's another hint: When navigating in the menus, note that you can use the wheel to switch between the menus. That's a lot quicker than moving up and down to reach the menu switching position. I'm sure you are already saving clicks by moving up (when you are at the top position) to reach items far down in the menu. Getting to them from the bottom, instead of from the top, is often far quicker.
Although all the relevant information for using manual lenses is contained in the manual as well, some may find this tutorial on how to use such lenses on the K100D useful: http://forums.dpreview.com/forums/re...ssage=24921509