Yesterday I was prancing through reddit when I followed this link: http://pvk.ca/
My stomach sank when I realized I wouldn't have the time to "follow along" (i.e. waste the day reproducing his results, checking facts, researching and following links) because I am about to start a lead-dev/PM position and need to work on SaaS and EA stuff. So I closed the tab and moved on to focus on what matters. It wasn't until 1AM that I realized what I have done; aarongough sent me a link to his toy prototyping language and I have just spent 5 hours reimplementing it in Lisp, in the process re-digging into the Self papers! (and discovering warts, but that's another story.)
I am an Adderall prescription away from leading a healthy productive life, without unnecessary knowledge about stuff.
What every programmer should know is the latency of the various memory types (cache, RAM, virtual) and their respective sizes.
Here's a nice graphic:
http://duartes.org/gustavo/blog/post/what-your-computer-does...