Searching AVR microcontroller!

Hi! I´m looking for microcontroller to my 7seg display tempmeter project. (LM35DZ temp meter and 5641AH (12pin, CC) led display). Anyone know good product to that? (I´m looking for microcontroller i can rewrite with my Arduino) I don´t want to use crystal in it, it has to be very easy to use. Anyone know controller like that?