In my own time, I’m one of the package maintainers for the Linux kernel in Debian, and I maintain the Linux 3.2.y stable series, which will be used in Debian 7.0. I try to get important bug fixes all over the kernel backported and reviewed for inclusion in 3.2.y and other stable series. I also co-maintain the linux-firmware repository, which collects the various blobs that Linux drivers may need to load into their devices.
In my day job, I look after the sfc network driver and ethtool, with some forays into the networking core and other subsystems that sfc depends on.