well no warrenty is void.
on a computer its a normal operating system.
on the ipod theirs no opening the ipod so the hardware warrenty is untouched and you can always use apples update utility to bring it back to regular standards,
in a PS2 its just like most mod chips and the warrenty would be void if the PS2 were still under warrenty
as for the Treo it was going to be a paperweight anyways
the PSP is something I was selling anyways
the DVD player was untouched it just came with linux because of how great it is.
and the router can also be brough back to its original state at any time.
I recommend using the router thing its really cool. and it already runs linux out of the box your just adding a more functional version of linux.
their just fun projects to make the time go by. im getting the new touchscreen ipod thats being anounced at the end of the month of August (hopefully) and being able to play videos on my old ass ipod photo is pretty cool