if it is the extended warranty from nissan its a good plan. the
independant onescan be very tricky though. you should ask for a copy
of the agreement to review at your convieniance if they shune from
that then run. I would read the fine print. I have seen many extended
warranties do stupid stuff. For example: your engine is shot so they
replace the engine and your thinking what a life saver but whene you
go to pick up your car you have a bill for somewhere between $100-$500
for things such as transfluid, oil & filter, coolant, misc hoses, misc
wire repairs, unforseen part modifications, replacement of parts
damaged by the engine overheating but these parts are not under the
warranty-the fact they wher damaged by a failed engine has no baering.
all this is above whatever deductable you agreed to.  and the engine
most likly will come from a wrecked car in a junk yard somewhere.

however with nissans security plus if your engine is blown you will
get a remanufactured engine from nissan and the warranty covers all
associated parts and materials. No junkyard crap here.

as for the computer senario I rarly see them fail anymore but if it
does your looking at a bill simillar to puting a new top of the line
desktop in your office!

Spat