Right... i've done a few searches... flushing the intercooler appears to be part of standard maintenance anyway, so it's not uncommon to do it. One that hasn't been flushed for 150,000 miles (like mine, probably) could more than like do with a good clean too!
As for how to do it, some people say use diesel. For this, I'll have to remove the intercooler, which involves removing the fan, the cowling, various pipes and needs two pairs of hands. This doesn't sound like a job for me, but i'll look it up in the Haynes to see how difficult it really is.
The other thing people suggest is either carburettor cleaner (of which I have a small amount) or Land Rover's special intercooler cleaner. I have no idea whether you'd need to remove the intercooler to clean it with either of these.
So... anyone have any advice on that subject??