I just installed Brad Choate’s MT-DSBL plugin, hacked slightly so that it checks against both the Distributed Sender Blackhole List and the Blitzed Open Proxy Monitor List. (Perhaps I should add SORBS?) Hopefully this’ll cut down on spam.
If this interferes with anyone’s commenting, please let me know.
Edit: it screws up mine. Off for now.
Edit: found the problem (my colo provider’s DNS is somewhat over-zealous). It’s back on.