Dave, I hope you'll be excited to hear that the Sheevaplug is still very well supported by Debian. I had one up-and-running with the latest version until very recently.

Here's a resource I used to set mine up: https://www.cyrius.com/debian/kirkwood/sheevaplug/

I have a hard time justifying keeping mine running, what with the Raspberry Pi and others being so much more full-featured and powerful, but it's definitely an interesting piece of hardware!