My wish would be that I could add notifications--as many as I'd like, and to different emails, like
at 50% disk usage email X
at 90% email X, Y, and Z.
That would be swell.
Thanks!
-=r

You can do that from your node, because on the host level of the linodes, the disk size is static.

At the profile manager if you create an 8GB partition, on the host it 100% full 8GB, although inside the node you just installed debian is it has 7.8GB free.

monit is a nice, lightweight monitor that can send notifications and/or restart or shutdown processes. It's generally available in the extended repositories (universe for Ubuntu, DAG for CentOS) of distributions.

Brilliant -- just what I was after!