PIC 16F627 MCUProduct Code: 29
£1.96 ex VAT
First, no external clock source is needed, the IC has its own on-board 4MHz timing circuit.
Also there is no need for a MCLR line. What this means is that you need NO external components to make this baby run.
1k of program space doesn't sound much, but try filling it!
An all round, popular performer with tons of potential, and very easy to use.