I haven't priced out a dual PIII system in quite a while because of the price of the motherboard which is usually north of $400, etc., etc.

I received a catalog from TigerDirect in which, on page 9, they say they are willing to sell a dual PIII 1 Ghz with RAID and 512 Mbytes for $999.99. That is probably as good a price as can be found IIRC.

Just a heads up. I have not affiliation with them.

While i realize that not everyone will be able to or be wanting to so, for the same price you can assemble a dual AthlonMP 1800+ yourself. I don't think anyone would doubt that that setup would be faster by a considerable margin, especially with floating point stuff.
I have just finished evaluating options for assembling a 16 cpu renderfarm and the above is what we will probably go for - 8 boxes with 2 Athlons, 512Mb, 30Gb each (data is kept on a seperate server so the disk is just for OS). Those boxes individually come to about 1200 Euro, which should equate to roughly a grand over in the New World.

Kai.

PS: I'm not trying to start one of those Intel -><- AMD flamewars, just wanted to show it can pay off to shop around or BYO.

You also need both an OS and NLE package that supports multiple processors too.