Other similar words I've picked up and heard when you don't understand/hear someone ...
- ¿Cómo? -this seems to be the most frequent, yeah? It's politer than ¿qué?, but how polite?
- ¿Qué cosa? - I don't hear this as often, but I'm generally confused about the contexts in which it's used ... because it doesn't seem like you would just use a phrase that translates as "what thing?" for any situation.
- ¿Qué? - this is generally very abrupt, it seems? Kind of like you don't just bark "what??" in English if you don't hear something.
Are there any others? Can you use disculpe/perdón/perdone? In English there seem to be so many ... "I'm sorry?" "What's that?" "How's that?" "Sorry?" "Excuse me?" "Come again?" "(I beg your) pardon?" "Pardon me?"
Thanks for your help!