The silicon wizards at Flylogic have certainly posted an interesting chip this time around. The Intel 4004 was the first widely used microprocessor. The logic gates are much larger than you’d find in modern chips. The unique feature is that each gate is designed to make the most efficient use of the silicon instead of the standardized shapes you find now. They’ve uploaded a full image of the chip.
For an introduction to silicon hacking, we reccomend [bunnie]’s talk from Toorcon and [Karsten]’s talk from 24C3. You can find many more posts on the topic in our silicon tag.