A high speed electronic ballot reader with a mechanical counter display. So you can stand there and watch it count. Then run it through a duplicate machine. It should say the same thing.
Appropriately documenting these occurrences should not be hard. Appropriately archiving them would be moderately difficult but would serve as the evidence of the final tally. The final tally of all precincts could then be calculated by any number of independent organizations.
There can't be any hard to understand computer voodoo, deleteable audit logs, or single vendor reporting the final tally. No one should trust that anyways.
Appropriately documenting these occurrences should not be hard. Appropriately archiving them would be moderately difficult but would serve as the evidence of the final tally. The final tally of all precincts could then be calculated by any number of independent organizations.
There can't be any hard to understand computer voodoo, deleteable audit logs, or single vendor reporting the final tally. No one should trust that anyways.