This is very interesting...
I've always thought of building something like the Rover (used in Mission Mars).
Linear Actuators work great and are a substitute to hydraulic/pneumatic actuators.
I'll think about building something like this (after my X std boards) -
RC Excavators
In the picture above, standard servos and acrylic glass is used.
Imagine using High Voltage Servos and Carbon Fiber !!!
and maybe using an Android Phone + Java app to control it.
That will take a lot of time, effort (and money
)