Okay so i found out a duplication glitch with hopper minecarts!
Look at the pictures below, please patch this dupe bug.
you make a an L shaped rail put 5 hoppercarts together on same rail peice
then throw any item in to the hopper by pressing Q, throw 3 in the hopper.
now you punch it, fake (item used) comes out, after you break it a ton of (item used)
drops.
this happens in survival & creative.
video proof of the duplication glitch
http://www.youtube.com/watch?v=RBseHC2v2b4&list=UUQwB4yvdk0Ka85lMD5iMpUg&index=1
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Confirmed.
Still happening in 13w06a
confirmed not fixed in 13w07a
Present in 13w09a
Present in 13w09b as well.
Works for higher amounts of hopper minecarts; works for stacks of items; no need to press Q to drop single items.