sadly i don't have any pics, but my brother's computer recently fried. He smokes while on his computer, and over time ash and grime had built up on the CPU's hsf. It was CAKED on...there was even ash in between the heatsink and the chip itself.
Lesson: If you HAVE to smoke while on the PC, clean the PC out once every other week. Every week if you use your PC often.
you shoulda seen some of the comps i cleaned out from work, luckly the whole warehouse has airhookups so i just blew the crap out of the insides with 140PSI.