Yeah, Tasker is marvelous. There's a plugin that can configure Google Voice for you, so I have it disable ringing of my home phone when I'm at work and re-enable it when I'm home.

I also have one that puts my phone in airplane mode when I leave it face-down at work, which I use to save battery while I'm in a closed area where I can't bring my phone. I wanted to try to get speakerphone based on the proximity sensor working, but hadn't gotten that working yet.

There's a Cyanogen release candidate out for the NS4G, but people are saying it's still rough around the edges, so I think I'll hold off on upgrading the ROM for now. I did root my phone last night in anticipation of a stable ROM release.

Re: the memory stuff, I'm pretty sure I did notice it slowing down my phone a bit. I was seeing 25+ apps running in the background, and, yeah, they weren't using CPU, but the system was using CPU to manage all of them, and it felt like it was starting to drag things down.

A lot of the apps that run are things I do want to have on my phone, but don't want to use a lot, and certainly don't need in the background. I just don't see why the OS is wasting resources starting up processes I haven't run yet since it booted, killing them off, and starting new ones. What's the point of that?

Anyone used this before? Apparently it's a more effective way of fine-tuning what runs in the background than using a task killer, though it requires root access.