Thanks Tom. I was thinking of using GlimmerBlocker last week. Thought I bookmarked it, but I must have forgotten about it. Safari Adblock, which is what I'm using now, sucks.

It turns out I had actually downloaded it already and had forgotten to install it. Doh...

Unfortunately since it's a system-wide proxy (and not Safari-specific), I'm going to have to do a bunch more work to try and get it working the way I need it to. I have been using LittleSnitch for years (a filter-based outgoing firewall). Letting GlimmerBlocker freely access connections means that any other application can also access those connections unfettered.

I've stumbled upon what claims to be a work-around which I'll read in the morning.