Here's a blog with pointers to several interesting 6502, 6809 and 68000 projects.
Of note:
Description of Daryl's SBC series of 6502 and 65816 projects
Ultim809 by msarnoff built on euro card protoboard using point to point wiring. just 14 chips, has Compact Flash interface and 512k banked memory.
N8VEM computer accepts Z80, 6809, 6502
John Kent's
System 09 - VHDL 6809 System On a ChipA Small MC68008 Computer System by Markus Wandel, just 23 chips.
Rossum's ultra-minimal and cheap
RBox, an ARM based games system