[GeeTwo]

2012: Our Rebound Rumble 'bot, T1G3R, was disassembled within a few months. I have managed to find a few intact recognizable pieces as we moved to our new build space, that are going in a historical shadowbox.
2013: We still have the lower frame and frisbee shooter. We took off the drive and climber, and added some push-cart wheels. We used it as a demo in the spring; not sure if anything was stripped since then. The hooks are going in the shadow box, too.
2014: We disassembled the ball pickup and kicker, though the hammer and the side panels are going in the shadow box. We still have the (mecanum) chassis that we keep around in case we ever decide we want a mecanum for prototype.
2015: We're still using one for demos; I'm about 75% sure it's the competition robot. The practice 'bot was mostly disassembled, but we'll probably put the KoP drive chassis back together before build season for prototyping. The pickup rake is going in the shadow box, and we may use the cover plate from the control board as the face plate.

Non-competition: Our air cannon was begun in 2012, and the current version still has the same nanotube gearbox and chains, tanks, and probably the drive CIMs and a few fittings, but the rest of it has all been swapped out at least once.