UMM, did you actually look at those speakers? They are 4" EXTENDED RANGE DRIVERS not tweeters. And they are $0.49 EA not $0.87.
Yeah, I did. Didn't mean to call 'em tweeters -- it just came off my fingers that way. $0.87 is the "price" while 0.49 is the "special price". Whatever. It's ridiculously cheap anyway.
They are buyout items. Presumably that means that they'll soon run out of inventory? Maybe I shoudl buy a bunch for the future just in case.
I am planing to buy a bunch and build my own surround system with them. I'l definitely post more info when I get them.
And as to your question about DIY sound, as I said, my friend at work spent about $40 dollars on speakers and BLEW AWAY his $400 JBL set. And by BLEW AWAY I don't mean that they were just louder. They had better/clearer sound by far. He brought them in to work to test them and I could definitly hear the diference.
Look here for some examples of what some people have done with these speakers. If you look at "Bruce's Array" you will see something similar to what my friend did.
Very cool examples. That long page is worth reading through. I like the coffee-can design although I don't think I'd ever built it.

The one thing I've learned about speakers is that I generally have to hear them to be able to judge the sound and decide to buy or not (regardless of price, recommendations, brand, etc.). But for this cost, a PartsExpress project sounds like a worthwhile project to jump into no matter the outcome.
I'd love to find a similar subwoofer alternative too.
Thanks for this information. I'd be really interested in hearing how you fare.
-pmc