[bmmayer1]

Almost every nonprofit--especially local nonprofits like food banks, hospice care, shelters, legal aid centers, etc--has technology issues. They don't have enough money to pay for IT of any kind, especially in hyper competitive markets like Silicon Valley, and their tech knowledge would be probably laughable to you. If you showed up unannounced at the offices of one of these nonprofits and offered to help them with any tech issues they've been having (fixing a website, making the printer work, etc) they would be most grateful. Of course it's better to ingratiate yourself to the hardworking teams over there by making yourself part of the community first, you don't want to show up like the messiah who's going to fix all their problems for them. Above comments address this.

[shrikant]

I would strongly second this.

I had some down-time between jobs a couple of years back, and used it to volunteer at a charity to help out with some basic IT work.

There was some indeed an element of fixing and securing their WordPress-based website, and sorting out their AdWords campaigns. However, the vast majority of the work (by time, not by difficulty) was cleaning up crapware from Windows laptops, getting Dropbox to work correctly across their machines, and sorting out their software licences after they'd been screwed over by a shady ISV.