Fastest solo ecto farm?

So I was wondering what's the fastest way to get ectos nowadays. I know there have probably been a hundred threads like this but couldn't find any in pages 1-5 (going back to november '10) and older ones are probably outdated because of updates.

I've been running a SoS Rt which is very easy to use and can clear pretty much anything, however smites take a long time (have to get lucky with spirits focusing one smite) I usually clear everything up to dune burrowers/smites and then resign because I feel killing beyond that takes too much time, and also I get bored . Anyway using Rt you end up killing a lot of graspings and enemies that don't drop ecto.

I've also geared up my warrior to try the W/Me (too late for rending aura ) smite farming, which seems a little faster since you kill more mobs that drop ecto in a short time.

So, which is generally considered fastest? I'm only talking solo builds and preferably short runs. I have access to every campaign, skill and profession.

I don't think there are really anymore really profitable solo runs. You could always try perma sin in topk.... I heard its pretty good there.

current game design and drop rates leads me to suspect the only really fast way is to buy them.

Farm for money not items.

I also do the spirit-spam UW ecto farm, and like you, I leave the smite crawlers because they're too much trouble. I'll sometimes drag my alt ele in with something like this (the warrior skills aren't really needed for the smites -- they're to get past the stuff I clear with my spirit spammer anyway) or this.
But:
1. It sucks against Skeletons and Nights (nights don't drop ecto, anyway, but they get in the way).
2. It kills everything at once, and I'm a firm believer in getting more drops if you kill things individually.
3. Isn't the common belief that Smite Crawlers have a 2% chance to drop an ecto, while Aatxes have a 4% chance? I'm not sure if going after the smites is really worth it.

It takes me about 1/2 hour to spirit-spam the Labyrinth, and I usually average about 3 ectos a run. That seems pretty fast to me. Other than that, ToPK ledge farming with an assassin seems to work pretty well for a friend of mine. I find it too boring, though, and my personal success rate there doesn't compare to UW.