Best mechanisms

[IKE]

2014-254 wheeled shooter due to it high release point and double collectors
2013 others have given good examples. I would add floor pickups from that year (33, 469, 987, 2054, a few others)
2012, 67 collector bridge adjuster arm. Built in could only collect 3 balls thus no penalty.
2011-the roller collector with release jaw. There were several examples, but this was by far the best tube gather and release mechanism.

2010 pincher gripper. It was a game changer.
2009-1114 elevating ball sorter was very cool and prevented jams.
2008-1114 ball collector puncher. Though even better refinements of that design came back for 2014.