OK, cell phones used to be candy bar shaped. We didn't even think about it, they were kinda all that way, except the cool Motorola Star Tac with that flippy cover over the keys, so it looked like the Star Trek communicator. But now, try to find a full featured candy bar phone. They are replaced by the querty keyboard Blackberry copiers. But that keyboard is only nice sometimes. The predictive text of the 9 key keypad in cell phones is so darn good. You can understand though that there are compromises in them, the geography is limited if the phone is not to be too long. That is where the clamshell is best, when unfolded it is twice as big. the slider is about 30% bigger, so the keypad is a bit cramped.
So I did a search on just these phones and found a couple, with somewhat anemic features. Smaller screens, weaker cameras, poor browsers. This is one that seems to appeal. It goes for $30, so is a consideration. The screen is good, but smaller. It is very thin.