I started clocking real money, admining unix systems, when I was pimple-faced and fresh out of high school. The trick is to run your own 5k shell-account service and drop a heavy resume on someone's desk :-)
You can always do your own things and "get experience", fuck these pricks man. That shows more initiative to real entrepreneurs who want to hire you later. IMO, internship just tells me you did your time being someone's in-house rookie.
There's a big difference between working for no money and working for any amount of money (or for equity). Even if they agree to pay you minimum wage you at least have a job to point to -- and a starting point for future negotiations. There is no raise so difficult as the one from "free" to "$x".
Another point I'd make is that working cheap like this is a deal that might make sense for a few hours, but which will make exponentially less sense as you do more and more work. And you'll know it, too. The first three hours of free work you do for someone can feel great, but eventually it will rankle.
[ I've moved the rest of this post to a separate comment. ]
You can always do your own things and "get experience", fuck these pricks man. That shows more initiative to real entrepreneurs who want to hire you later. IMO, internship just tells me you did your time being someone's in-house rookie.