OpaVote provides a few other counting methods that are less commonly used, and these methods are described here.
The Coombs method is just like IRV, except that a different technique is used to select a candidate to eliminate. With IRV, the candidate with the fewest votes is eliminated at a round of the count. With Coombs, the candidate with the most last place votes is eliminated.
The Borda count uses ranked ballots, but votes are not transferable. Instead, a score is generated for each candidate from the ranked ballots, and the candidate with the highest score is the winner. If there are N candidates in the election, then each candidate gets N-1 points for each first place vote, N-2 points for each second place vote, and so forth.
The Bucklin system is also known as the Grand Junction system (where it was once used) and American preferential voting. The voters rank the candidates and a candidate receiving a majority of first choices is declared the winner. If no candidate has a majority of first choices, then a candidate receiving a majority of first and second choices is the winner. If more than one candidate has a majority of first and second choices, then the candidate having the most first choices is the winner. This process is repeated for further choices as necessary.