Knobbies: A Good Commuting Tire

I just got through my first week with my 10-speed back on the road and it has been a pleasure to ride.  I think I cut about 10 minutes off my commute and it was just easier and smoother.  I cannot, however, stop worrying about flats.  The streets of NYC are heavily used and though the DOT has done an impressive job trying to stay on top of the local roads, the streets are often pock-marked, covered in glass and other particles--especially the backstreets I ride.  Furthermore, cyclists are usually consigned to the edge of the road where the road comes apart first and all manner of refuse winds up.  I rode the mountain bike all winter long--a Schwinn with the knobby tires it came with, probably cheap nylon--and I never got a flat.  It's not the first time I've had the experience, simple, cheap, nylon mountain bike tires are pretty tough.  It's actually rare to get a flat as long as there is some decent meat on the tire.  It seems that "meat" on a knobby tire beats high-tech substances on thin, smooth road tires.  Like everything in life there's a trade-off--you lose speed with knobby, trail tires, but a mountain-type bike is strong.  If you do not have really far to go (a few miles) and money is tight, it is a very durable choice.  I just care about keeping maintenance at a minimum.  I try to do as much of my own as possible.  I am not especially mechanically inclined, but with time, interest and resources everything can be learned.  Some things make more sense to learn and do than others.  I am not so great at truing my wheels or building them, but brakes, fixing flats, maintaining hubs, bottom brackets, some derailleur adjustment, etc... that I can do.  Naturally, the less time spent doing so the better.  The tires on the road bike are relatively new.  I look forward to seeing how they fare.