>1) Is NetBSD using the L2 cache on my G3 daughtercard? How would I
>know?

...
CPU: 750 (Revision 8202)
total memory = 65536 KB
avail memory = 51252 KB
using 2048 buffers containing 8192 KB of memory
mainbus0 (root)
cpu0 at mainbus0: 1MB backside cache enabled
...

:-)