My school's CS grad students [0] currently get a net stipend of $17,664/academic year ($19,188 stipend minus $1,524 in mandatory fees) if they are either a teaching or research assistant. In my college town, that's a tight budget but doable with a bit of effort

However, given the state of even the CS intern job market, there's an interesting possibility where grad students could pretty easily make more in the course of a 10-15 week summer internship than they make over the course of an entire academic year (not counting the value of the tuition remission).

[0]: https://www.cs.purdue.edu/graduate/financial_support/assista...