annoying metallic rattle/jingle

I keep hearing this metallic rattle from the driver side whenever I drive on rough pavement specially on the freeway.
It's pretty high pitch and seems to be coming from either the driver door or the front driver side
wheel. It reminds me of the noise my old honda civic used to make when the brake pads were
getting low. Anyone experience a similar thing? I only have 5K miles on my 2006 Prius.

thanks

-adriano

PS: search engine doesn't seem to work anymore for me. I keep geting giant my_sql error messages,
I hope I won't be forced to use a microsoft browser to search this forum...