For people who don't know him, or what he stands for, you can read up on him on wikipedia or his own web site. I know him as a former HP employee where he started Debian. He's also the founder of the LSB, busybox and a great evangelist of open source in general, up there together with ESR and RMS.
You can find him (very) active on certain discussion topics on slashdot, but he's always very willing to help anybody out. When I had some open source related problems myself, I turned to him for help and he didn't leave out cold. I can't say who else is so much available, that approachable in the OSS scene other then Bruce. He deserves your signature if you care about anything OSS related.