I'd like to know how to say the pound sign in Spanish. :-\

"Símbolo de libra" or simply "libra"

Thanks for the reply. I looked up libra and it means pound as in weight. What I mean is this symbol: # Is this also "libra"? Thanks.

In Spanish "libra" means:
1.- Currency
2.- Weight measure
3.- Zodiac sign
4.- third person of verb "librar"

This symbol # known as a pound sign or simply pound (on the telephone) in the US. It is also known as a hash or hash symbol. If you say "pound sign" in the UK, they will think £ as in the sign for Sterling Pounds. "Pound sign" could also mean Lb, used in the US to represent the weight of one pound.

In México, # is known as a gato or símbolo de gato, in Spain it is most commonly reffered to as the almohadilla. Some people also use cuadradillo or numeral to say this symbol.

Thanks to the three of you for your answers. Sorry I've been away so long and I couln't respond, but I was on vacation. ;D Anyway, what I meant by pound sign is the "pound" on a phone #, so I guess gato is the right word for me. Does anyone know if it's ok to use gato in other parts of the world besides Mexico? or would they think I mean cat?

As far as I know, gato is used only in Mexico (for this meaning). I believe almohadilla is fairly common too.

In Spain, its "almohadilla", like Tomisimo says.
I never heard "gato"

Yes, I'm pretty sure "gato" is only used in Mexico (in this sense of the word). [miau miau]