[Lil Blue Versa]

Hey everyone, having some serious problems with our V. We have a versa s, 1.8l hb, 6 speed. my brother was driving home from a park today, and a FEROCIOUS knocking noise started happening. i generally consider myself rather vehicle savvy but this one is beyond me. the noise occurs when the clutch pedal is depressed while the car is in motion. it knocks periodically. (the knocking speeds up and slows down depending on how fast it is being driven, faster speed, faster knocking, and vice versa.) the knock can sometimes continue when the vehicle is in gear so i'm not sure it's clutch related. the transmission never slips. the noise also occurs when we turn left, or jiggle the steering wheel enough. it sounds like metal slapping metal, and a lot of creaking/groaning has started coming from the front left tire. it seems like a hub problem to me.. the breaks, tires, and steering assembly seem to be okay to my knowledge.. and the noise disappears when we accelerate at all..

any ideas on what it could be?