Keeping Out Street Noise / Sound-Reducing Windows

Dear Audiogon:

In my urban (Chicago) home setting, the single biggest negative impact on my listening enjoyment is the outside noise from the street that intrudes through the windows of my listening room, which faces the street. I don't have the option of moving to a room that faces the alley, and I'm trying to think of ways to damp the street noise. Mostly it's cars with no muffler/under-performing muffler (or "high performance" street racer/ricer style "upgraded" mufflers, which are in a class of pain all their own). And of course the "boom cars" cruising by slowly, to make sure I don't fail to appreciate every note of the driver's current obsession. And of course the usual urban mix of sirens, shouting, horn honks, ice cream trucks, car alarms, etc. (And no, I have no interest in moving to a quiet suburb. Been there, done that for many years, and not inclined to repeat.)

I'm thinking maybe the answer is to get sound-reducing windows. I previously installed Loewen Tranquility windows in a home I used to own that, while in the overall quiet suburb of Libertyville, IL, had a rail line running along the back lot line of my home, and the trains were signaled to sound their horns directly behind my house (about 200 feet from my bedroom) to warn vehicles at a nearby grade crossing. Also had a massive tree, full to exploding with starlings and other chirping avians, that overhung the roof right next to the bedroom windows. I had the Tranquility windows installed, and they did a very decent job, especially with the chirping birds (they cut the high frequencies much better than the low, as I would have expected). It was always fun to demonstrate them by cranking them open and closed and hearing the bird-chirp din alternate between overwhelming (when open even a crack) and completely unhearable (when closed). It was a lot like that scene in Ace Ventura: Pet Detective where the hero demonstrates the sound-blocking ability of a murder victim's glass balcony doors (minus the hilarity).

For those who don't know them, these Loewen windows (http://www.loewen.com/Home.nsf/news/PLEE-6E7SBR) have 1/4-inch (!) thick inner panes, weigh a couple hundred pounds each, and cost one billion dollars each (OK, I kid; but I think it was over $3,000 to have one double and one single window installed, and that was ten years ago).

Anyway, what do you think? Any experience with a better sound reducing window than the Loewen Tranquility? Any better alternative? Anything I can buy to stuff in the window frames and absorb sound in a reasonably aesthetically pleasing package (in my weaker moments, I envision apparatus involving velcro and very thick felt pads in designer colors).

Thanks in advance,
Jim