Mysterious clunking sound when braking

My wife's '96 Sunfire recently started producing a clunking noise when braking. At first I thought something heavy was rolling around in the trunk. The trunk is empty and the spare tire and jack are securely stowed under the floor compartment. The noise occurs only once, always at the very end of braking, conspicuously at the moment that the inertia shifts from deceleration to a resting position. It sounds like a dull "clunk" from a heavy object, and it can actually be felt in the driver's seat. The sensation and sound seem to be coming from the driver's side trunk area. I have lowered the rear seat and there is no effect. It does it whether the trunk lid is open or closed. I have removed both rear wheels and hubs, thoroughly inspected both drum brake assemblies and all seems to be normal. The struts are new as of four months ago, so I am fairly certain we aren't hearing bad shocks. The exhaust system has the expected amount of play and collides with nothing. The gas tak is secure as well. Frankly, this is starting to drive me out of my skull. I am not sure what is worse- worrying that it is something major, or simply not being able to track it down.

Please advise.

That sound you may be hearing could be a shift solenoid. I don't know a whole lot about them, but the mechanic told me that it's nothing to worry about. If we are getting the same noise, it happens right around 10 mph, when the car shifts back into 1st gear. I'm assuming you have an automatic like I do. I haven't had the chance to look into seeing how much it would cost to repair yet. I hope this may be a possible starting point for you. Let us know what you find out.