Since writing the journal entries below, with their emphasis on time stretching sound, I've been informed (tip o' the Hatlo Hat to Brian McLaren) of another excellent time stretching program. This one is optimized for extreme time stretching - that is, time stretching from, say 5 to 1 million times the length of the original. It's FREE, it's for Windows and Linux, and it's by the young Romanian programming whiz Nasca Octavian Paul, author of the free, very deep and useful (and microtonality capable) ZynAddSubFX software synthesizer.
This program is called "Paul's Extreme Sound Stretch" and can be found at http://hypermammut.sourceforge.net/paulstretch/. I've tried the program out with a number of sounds, and the results are VERY nice. There are a number of settings too, so tweakers will be very happy with this program. Like Harry Partch said of one of his instruments, "It does only one thing, but that thing it does very well, indeed." I especially like the readout on the "Stretch" parameter - it tells you how long your stretched time file will be. I loaded a .46 second recording of some starlings recorded a few days ago in Texas by Catherine into it, and in the most extreme "Hyperstretch" mode, the readout said that the sound would last 1458 years 237 days. Given my interest in impossibly long durations, you can understand how the idea of this tickles me.
So if you're at all interested in sound design (or just plain having fun with sound), you should add this little puppy to you collection. Highly recommended!
And by the way, for users of ZynAddSubFX, it's just had a major upgrade and revision, and it's been greatly improved. Here's the link: http://zynaddsubfx.sourceforge.net/. Enjoy!