I've seen a lot of calls here for paper ballots, and while paper ballots are a step in the right direction, they're an incomplete solution to the voting system problem. I assume that when people talk about paper ballots here, they're referring to voters marking paper ballots with pens or pencils.
Problems with paper ballots:
Overvotes (see FL 2000--overvotes happen on paper ballots and can invalidate large numbers of votes)
Unclear marking of votes (voter marking problems, disputed recounts over whether some marking on the paper is a vote or not)
Proposed solution:
Electronic machines which guide voters through the voting process running open source software, then allow a voter to print out an official ballot clearly showing the voter's votes. The voter can then check the paper before dropping it in the ballot box, where it serves as an official ballot. Counting could be done either by using the electronic count and supplementing with random audits or by counting the official paper ballots by hand and/or machine (perhaps the printed ballots could include bar codes for fast counting).
Of course, even if we had perfect voting systems, we would also need to counteract voter suppression of various sorts (ID requirements, voter roll purges, prohibiting felons who have completed their sentence from voting, etc.), and make election day a national holiday, and reform election systems in other structural ways as well.