What is the phone called that slides into a keypad and into a keyboard?

I want a new phone like that but I don't know what its called!

there are tons

rumor

scoop

gravity

duo

matrix

touch pro

lybra

LG Rumor?

Scoop?

Samsung Gravity?

There is one from AT&T called the pantech matrix....it would help if you knew who the carrier was.

There are many kinds of phones but the only one that I know the name of would be the Rumor.

i think the samsung gravity, its really cool.. i want it.