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I use NHC's Prism which works on PPC and it is (at least for me) very snappy. No idea how it compares but I have never had to wait 12 hours to convert anything with it.
 
Alternatively you could try and hunt down Elgato's Turbo264 dongle. Not the best quality conversions but fine for iPods and the like. Even my Mac Mini G4 converted formats without breaking a sweat and it is much quicker than Handbrake.
 
@ roadbloc:
Thanks for the tip!

Does this do video, too? The one I linked is for videos. When you convert videos with e.g. Handbrake on a PowerPC-Mac to h.264/x.264 it can take 12h for 23min. of video. Of course divx will be faster or just use other presets, but the quality will also be much worse, with small bitrates.

@ weckart:
Of course and other external Video-(A/D or D/D)-capture/converters that already record in a compressed format, but for better quality and certain sources one wishes to use a software that one can choose all parameters (and also doesn't do it on the fly while recording like some video-capture-devices). The reason why Handbrake is so slow (iMovie is even much slower with worse quality, because the codecs are older) is not the software, but the slow CPU of the PowerPC-Mac (23min. DV-video to x.264 with Handbrake: ibook G4 1,33GHz = 12:30h / Mac Mini 2012 Dual 2,5Ghz 7min.).
I am sure you know all this, but I wanted to clarify it for others that might come here and are not into the topic that much.
 
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