Next week the Mill seminar that I've been running this semester reaches Considerations on Representative Government (included in Gray's On Liberty and Other Essays, which is the set text for my course). Anyone with passing familiarity with this work will know that one of Mill's most (in)famous recommendations is a system of plural voting, according to which the poor and uneducated (although not those living on welfare benefits or the illiterate) would get one vote, but other more educated citizens would get more than one vote.
This idea generally strikes students as repulsive - correctly so, perhaps - but one point I try to stress is that, at Mill's time, this was a progressive proposal. In other words, he was not advocating taking away anyone's vote (as a proposal with the same content would today), but extending the vote. He wanted to give the less educated some power, which seems a clear improvement on none. (Though I can see why someone firmly committed to political equality might think it better not to go down this road.)
This Wikipedia entry is remarkably interesting though. It was not until the 1948 Representation of the People Act (first applied in the 1950 general election) that the UK abolished plural voting. Belgium also practised plural voting, something like what Mill proposed, between 1894 and 1919, apparently to limit the impact of universal suffrage. In practice, universal unequal suffrage may be a stepping stone towards universal equal suffrage, rather than a step away from it.