Long-horned beetle, Xestoleptura crassipes (see update below), native.
My daughter found this beetle in the bathroom. Her first pet, at least that was her plan. It's a native cerambycid (long-horned beetle) with a cool name, Leptura obliterata. It's a boring beetle whose larva feeds on dying or stressed, often fire-damaged conifers. As a native species, it most likely doesn't feed on healthy trees (see this source).
It's those interesting beetles from afar that cause so much damage.
Sadly, after some encouragement, my daughter let the beetle go. Last night at bedtime she asked me what I thought he was doing now.
Update: Ted at Beetles in the Bush has identified the beetle as Xestoleptura crassipes. (See his comment below.) Thanks, Ted!