We're the Portland State University Summer of Code team, hoping to participate in a third year of this fine activity. In the past two years, we've successfully mentored 11 students through projects in a variety of areas ranging from the immediately practical to the forward-looking esoteric.
Our specialty is projects that clearly benefit the student, the open source community, and society in general, but have no obvious fit in the standard mentoring organizations. In particular, we tend to focus on small-scale or individual, risky but promising open source 'seed' projects that we think will grow into something great.
We have a tendency to mentor projects in open technology, including Linux kernel driver work and open hardware/software systems work with a solid code component. That said, a number of our projects have been at the applications level as well; one of our strengths is the ability to track down mentors for a wide variety of different kinds of activity. Portland, Oregon is an amazing place, and we're lucky to have access to a strong, diverse open source community.