Microcontroller for the hobbyist?

TomTheGeek writes: "I'm a programmer that's done some assembly language before and would like to start programming microcontrollers. I've heard about the BASIC Stamps from Parallax, the PIC series from Microchip, the MAKE Controller Kit, and the AVR series from Atmel but they seem to be focused on a development board that is too expensive to dedicate to a single project. Having an expensive development board is fine but I want the microcontroller to be cheap (<$10) enough that I don't have to disassemble my previous project in order to start a new one. I'll be doing the programming in Ubuntu so compatible development tools and drivers are required."