Replacement: Although there is no direct replacement, you may want to check out the ATmega328. This page is for reference only.
Description: Atmel's ATMega168 8-Bit Processor in 28 pin DIP package. 16K of program space. 23 I/O lines, 6 of which are channels for the 10-bit ADC. Runs up to 20MHz with external crystal. Package can be programmed in circuit.
Documents: Atmel Datasheets