FWIW Brazil has mandatory voting and many parties. Two of them are dominant, but there is a much greater level of awareness for other parties than here in the US.

If you don't vote in Brazil a lot of the things you normally do involving the government become complicated until your pay a fine and fix your status. Anything involving government issued IDs to social security and unemployment benefits are cut off until you "regularize" your status by paying the fine for not voting.

My biggest complaint is that the system forces even Brazilians living abroad to vote, which is a big pain in the ass when you are abroad since you aren't aware of elections (it's easy to forget) and you need to find the nearest consulate and figure out how to vote. Every time I've returned to Brazil I've had to go and fix my status by paying the fine for not voting in the elections that occurred while I was out of the country.