Non-literal "de nada"?

Question

In Spanish "de nada" is "you're welcome"; but a literal meaning of it is "of nothing" or "think nothing of it."
Is there a way of saying the same thing in a way that informs the listener that it was MORE than "nothing" (maybe even an imposition, something above and beyond the "call of duty"), while still being polite or gracious about it?

Answer 1

I sometimes use the following:

a mandar

1. loc. interj. U. para declararse dispuesto a cumplir los deseos de otro.

So when someone tells me to help him/her with something and they thank me for that, I can reply "a mandar" to express something like "I'm here for whatever your orders are". That does not carry the implication that you have done nothing, just that you declare yourself ready for commands. I'm afraid it does not carry the sense of "it was a challenge" either.

Now that I think of it, you can also answer a "gracias" with:

Cuando quiera (quieras)

Thus you avoid saying "de nada" and so you imply that what you did was really something, but also you say that he/she is welcome to ask you a favour any other time. Maybe it's the closest to "you're welcome" in Spanish.

Finally you can also answer with:

Un placer

This way you also avoid saying that what you did was nothing, just that what you did was a pleasure.

Answer 2

a way of informing the listener that it was MORE than "nothing," maybe even an imposition, something above and beyond the "call of duty"

I think the expression you're looking for is:

"¡De nada, me debes una!"

(Literally: "It's ok, you owe me one").

While kind of informal, it is polite enough for most contexts.
It is better not to leave the "de nada" out, because that might be seen as rude, and pass a negative connotation onto the "me debes una" part.
When said as above, it doesn't necessarily mean that you actually expect the other person to repay the favor; just that this was a moderate effort on your part, that it was not "nothing" --as there wouldn't be anything to "owe" if it was "nothing"--, and that you want your listener to know.

Of course, if it was really an imposition, you can leave the "de nada" out and say "me debes una" with a straight face. Your listener will know that what you did for them was way beyond of what you'd usually do for anybody.

Answer 3

«De nada», «por nada», «no es nada», «no hay por qué darlas» o «no hay por qué», «no tiene importancia», «las que tú tienes», «¡olvídalo!», etc., are all courtesy formulas to say to the listener that is not in debt with you, no matter if your help was tell him the exact time, lend him a lot of money or save his life in a dangerous situation.

I agree that «ha sido un placer» or «a mandar» is less explicit in this sense, but mainly send the same message (that listener is not in debt with you).

There are not courtesy formulas when help is really not for free. If you say «me debes una» can sound well-mannered or rude according to the tone of voice and the context, but it mean what it says, it is not a polite expression. For me. the expressions «ya me devolverás el favor» or «hoy por tí, mañana por mí» sound much better because the connotations that you grant a longer term to pay the favour, but anyway they are all just warnings that the favor should be checked in the debit list ... and you expect some correspondence.