Improving performance of HTC Magic I have installed Cyanogenmod 6.1 and it's OK - better app compatibility, and stable - but it's slow (and USB SD-card mounting doesn't work, but maybe that's an app or something).

What can I do to speed this thing up?

Ginger Yoshi 1.5 sounded like a good option, but I got errors when I tried to flash it.
To answer the question - to speed that thing up you need to roll back to CM4 or another Android 1.6 based ROM.

I have a Magic and have used several ROMs including CMs 4, 5 and 6.  It is unfortunately hamstrung by its first-generation hardware - you simply are NOT going to get both features and speed from this phone, period.

Android 2.x ROMs do not make the Magic faster.  With all their config options they can make some things appear fast but this comes at the cost of performance in other areas.