Zilog Z8 Encore! (don't blame me, the exclamation mark is part of the trademark) I'm repeating myself, but the easiest microcontroller for beginners and hobbyists. $20,00 programming cable with a free C compiler / Assembler / IDE. Or you can make your own programming cable with an rs232 level shifter and a diode.
There's no need for ZIF socket programmers. Single pin debugging/programming means a single 3 pin header off of your project board can be used for high speed in circuit programming/debugging. Chips are cheap and there's little firmware differences between the full line of controllers. If you want to move your project to a higher pin count controller, no programming changes are needed. Large list of supported hardware blocks.... SPI, I2C, IrDA, UART, ADC, DMA controller, all GPIO can sink or source current.
Programming cable connected to a project board:
**broken link removed**