There are some 12 volt power supplies that can be used in place of the
standard AC supplies in most desktop machines - but they may cost more
than a suitable inverter.

OK

Well it sounds like that maybe rather than "swimming
upstream" one should go ahead and just buy/use laptop
PCs

Im not really a big fan of laptops cause they cant be
serviced easily, etc..... but sometimes I guess one
cant fight the economies of scale of some things such
as laptop production and prices.

So....sounds like it just best to use laptops on sail
boats and such cause they are cheaper, use low power
components, etc