If you haven't experienced a spinthariscope, I can highly recommend it. I bought one as a Christmas present for a buddy and we both enjoy its demonstration of radioactivity.
You really have to get your eyes adjusted to the dark to see anything with the spinthariscope. It ends up looking mostly like static on a green crt, but if your only reference frame is a cloud chamber, the volume of particles that are emitted from such a weak source is pretty remarkable.