Hi guys, I wanted to share this little discovery with you: if you have an Xrite Colour Checker you can download this
for free. It is a nifty programme that contains a Lightroom plugin. Install it, shoot your colour target in the light you want to calibrate for, import the shot in Lightroom (2 or 3), export to the Xrite plugin and it will create a colour profile for you. It fixed a lot of headache with my 5DMI, which has crappy Lightroom profiles (the reds were orange, the grass looked like plastic etc). Of course this only applies to RAW captures.
Nerdic but useful!