Hi guys I'm new here (this is my first post).
I have a Rockwood body shaker I have had lying around for ages (same technology as a Buttkicker).
I plan on hooking it up to an old amplifier (any 4Ohm with decent power will do) and conecting it to the sub output on my sound card, I might add alow pass filter if I get too much rumble. You can get these things for an absolute fraction of the cost of a Buttkicker (about 40 euros), they are designed for home cinema and cabriolet cars. I will simply screw it underneath my chair (it has a wood base).
I'll let you know how I get on when I get round to it but I have other higher priority things on the project list at the moment. I have a feeling it will have very near results for a fraction of the cost.
It also seems the Aura Bass Shaker is another popular alternative.
Cheers
Ben