...I've bought speakers for the iMac.

I went into a "computer market" place today and almost the first stall I saw had a couple of the original 15" G4s, one of them with the speakers, and the vendor let me have the speakers cheap because they were untested and he thought the plug looked a bit loose (which it is). But they work perfectly, and even have the front grille things which are as rare as hen's teeth, I just need to add a bit of sleeving on the cable. VERY pleased!