KRM

My scoob (96 STi) has developed the most annoying rattly noise in the world! It seems to be coming from around the front passenger side area, possibly down around the wheel. It's quite loud and really noticable inside the car when driving slowly (like 1-2mph slowly) or about 15-20mph over bumpy tarmac. It sounds like something is coming loose and knocking but I can't see anything that's not tight.

Anyone got any ideas?