there's another thing I forgot to mention that might be worth to look
into when it comes to GIMP on Mac OS X. The new compositing code that
Helvetix added already provides the framework for making use of
Altivec instructions. If someone has access to a G4/G5 and has some
experience with this stuff, it shouldn't be hard to add Altivec code
for the most common compositing routines.
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