Lycanorukke
SOC-13
Well, in the Real World, there is a 40-foot container loaded with millions of Legos that is sending a steady stream of them washing ashore on the shores of the North Sea, so your post is not that far-fetched at all.
The rubber ducks (more correctly the Friendly Floatees) have been used to map ocean currents by observing where they show up, and the Legos you mentioned have become somewhat of a collectors item. So instead of ocean currents they are used to map 'gravitic anomalies' or the like.
Also, remember that all of this space debris is not really drifting, but moving at high to very high rates of speed.
The other side of the problem is how to have the PC's 'meet' space wreckage at slow velocities enough so they can investigate. If they are zooming in at a 100kps from the jump point they can't just slow down and stop to have a look on a whim. By the time they even notice the flotsam and say 'Whats that?', it's busy disappearing into the distance a behind them.