How do *you* read/handle a large (several GB+) datasets? What about huge (1TB+) ones?

Hey all, I'm interested in learning what folks in /r/machinelearning use to handle large datasets.

Initially I was just going to ask a basic question as to what tools and methods I should use for tackling such problems, but I thought it would be better for everyone in general if people shared their workflows. That way it is more of a discussion and others can comment and recommend alternative methods.

So, how do you read / handle large datasets when working on your ML problems and research?