Heh, glad to have helped. It was something that I thought would be cool, though I didn't think you'd go for it as the mod might get slightly complicated (crafty? as in craftsmanship
) Glad that the idea appeals to you.
This was brought up a few weeks ago in the Keyboards section;
http://www.kickstarter.com/projects/1624347034/talons-programmable-computer-keyboard-with-integra?ref=liveWatch the video, and go to around 1:10. Despite the failings of that particular keyboard, I think the guy got the chair mounting right in terms of ergonomics, although you might still want to test the positions out. The keyboard itself not withstanding, the ergonomics of how he splits the split halves on the chair are pretty sound.
It's a decent reference point to begin with when planning your orbweaver mounting. General rule of thumb, you want to be able to sit back comfortably and be able to reach for both the orbweaver and move your mouse at the same time without putting any stress on your shoulders.
There's also something else, maybe a little complicated, and its something way out of my capabilities - the possibility of making the orbweaver wireless. It's a thought, but to be honest, I'm not sure its worth the trouble (actually, given the price of the orbweaver, such a mod will cost more than the orbweaver itself. Not worth pursuing unless its a curiousity/technical pursuit/learning purposes). It's probably easier/faster/more affordable in the long run to so some creative cable routing and keep an eye on Acidfire's creations in the making stuff section (which would likely have wireless) if this option is to be pursued.