Hi Michael,
I haven't seen any functionality yet that will do this, but I did come across an already existing idea last week that would help with this: http://lithosphere.lithium.com/t5/customer-ideas/Automated-quarentine-moderation/idc-p/98216#M5358. Instead of letting users know that an item has already been reported, the idea suggests moving it to a quarantine state after a specified number of reports thereby limiting views and reports.
I'd love to hear if anyone else has any workarounds too. Our community has similar issues!
~Jillian
