Any computer science students reading this should go directly to http://code.google.com/summerofcode.html and read about what Google's doing this summer.
But, if you're still reading this, I'll recap. Google is funding student work on open source projects. Basically, open source projects register with Google and specify defined tasks they want to have completed on their projects. Students apply to complete a task, and if they're approved and actually complete the task over the summer, Google pays them money.
You may not get your college to actually count this as an internship, but you'll get some great experience, earn a little money, and support an open source project at the same time.
So why are you still reading this? Go apply!