Nidec outline how to manufacturer an extruded aluminum heatsink like the kind sold with just about every Intel processor, in this patent application. If you've ever wondered how such a complex fin shape is squished out of a die and formed from raw aluminum, you'll like this. "HEAT SINK FAN, AND RADIATOR MANUFACTURING METHOD"
FULL STORY @
PATENT (http://appft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch-bool.html&r=1&f=G&l=50&co1=AND&d=PG01&s1=20080180912&OS=20080180912&RS=20080180912)