Nice. I've also found http://buildyourcnc.com quite useful, but am still to actually get around to making one for myself... kinda is a luxury when I use a Biesse Rover at work almost everyday and am responsible for the programming / maintenance of it, and seem to have a never-ending list of things that need to be done...
When you feel you really need a home router, you will have a Biesse Rover you can use to make the parts for your project. That's a real luxury!
The reason I posted the Mantis and not the one from buildyourcnc.com is that the Mantis is student-grade: simple, cheap as hell, small volume (not only working volume, but also external envelope) and easy to align by design. You could probably build it using only manual tools.
I couldn't tell from the site if the machine could be used for machining something other than circuit boards; you seem to have experience here, can you comment about it? I would certainly love to have one of these guys in my shop. Just don't need circuit boards cut.
You can cut a lot of stuff with 3-axis gantry machine. I use it to cut spearguns of my own design for example, It's a bit tricky to make a precise machine with a lot of Z-depth though, but you can turn around the material and mill from both sides (double the depth in that case). Pretty much anything can be done on that machine. In hindsight, I should have maybe gone with a fourth axis too (rotational) since that would suit me more in this case.
I built a CNC 1.7m x 1.3m with 800+ IPS for ~2000$ - with a lot of googling and persistence. Ping me if you want to build your own, I'll give you details, it's really not that hard at all.
No, nothing online. It's a standard gantry 3-axis mill though. Pretty much all info to build your own is here: http://buildyourcnc.com/ I wish I found that info before!
I wonder if you can also use this framework to include a 3-D printer.
It's the same XYZ axis control, I think all you would need is a different head. You may be able to even mount both heads at once, offset from each other.