Permanent Magnets are the way to go.

[Bob]

Well its very Similar to what he had.... but not the same at all
this unit only had one disk... and it had magnets on the disk... the hand crank came out of the center of the disk with a simple "L" handle on it....
 the coil of wire was mounted on the right side by the POST that ishued the arcs....
...there was NOTHING touching the disk at all... no brushes or anything... the handle had bearings on it mounted to the 2"x2" wood posts and the handle turned the disk ONLY...
... memory is fuzzy at best now after all these years... but that is the way I remember it...
 it could have been a Store bought Winhertz generator .... in fact it probably was... but its not what I remember.... it wasn't that complicated.... just something he through together for demonstrations for class...
at the time we were living out on this property in the old place,with no electricity, just battery power from the cars... it was my job to hook up the battery cables to the car when Dad got home so we had 12vdc lights and TV ...(it ran off 12vdc)
 in all the years doing that we never ran the battery in the car flat... but we were very carefull not to run the TV long... back up lights from pickup trucks and utility lights were our light source as well as Kerosean lamps...the main lamp was a 2 mantle white gas lantern.... it usually stayed in the Kitchen!...
....
So Obviously , I was thinking about making a generator for the house something that didn't take that much power to turn... perhaps a windmill or something.... but I never did find magnets I could use for it....
 probably a good thing as it would have fried the lights I am sure ! HAHAHAHAHA
....
Bob......

[Manta]

Maybe not a Wimshurst machine as Bob refers to a coil of wire. This would seem to indicate an electromagnetic machine (magnet passing a coil) whereas the Wimshurst machine is electrostatic.

Note also,  from the wicki,

..A typical Wimshurst machine can produce sparks that are about a third of the disc's diameter in length and several tens of microamperes...

Bob's machine sounds like some kind of lab demonstration model of an dynamo.  But that wouldn't account for he long arcs.

Dave
(Manta)

[Bob]

you know.... now that you mention it... what I REMEMBER just doesn't Add up !
I don't see how you could get Mega voltage out of that system to begin with....
 if you consider the new wind generators that have a disk with rare earth magnets  glued to it that spin past sets of coils  the biggest ones only put out 14vdc and what ever amps ...to amount to 400watts to 800watts max....
and from what I remember all they are is a fancier version of what he had.... but maybe the wire coil was different I don't remember looking at it real close...the mechanics of it are what intrigued me!
....
maybe he had really thin wire and  hundreds of coils... like in a car coil to up the voltage
....
HAHAHA now you've went and done it... I'm going to have to build one now just to see if what I remember is right ! ....
....
 there's a funny thing about memory.... it gets modified over time...now I am courious as to how much  it has been modified !
...
I know that he left the static generator there and a few of us snuck back into class at lunch time
and played with it.... I was really supprized that all it was was a motor driven Rubberband on rollers
and some wipers near the rubberband.... how they were attached I don't recall but I know I dropped the dome and that got the teachers attention and got us all in trouble ! HAHAHHAHHA
having to write  "I will not sneak into the classroom at lunch time without permission" or what ever it was, 500 times was really hard punishment ! LOL ! couldn't do nuthin till it was done ...man that was tough !  HAHAHHAHHHA

... I'm wondering if I didn't confuse the 2 machines one had a light bulb   and I thought BOTH made big sparks.... but thinking about it I don't see how that thing could have made big sparks
.... maybe with a Lidance jar or 2 perhaps.... but that would be indeed deadly !
...
I'll have to give it to you guys   I think you convinced me....  I don't think it'ed fly either!
hehehehe
... but what did I see way back then ? hummmmmmm
...
Bob...

[Manta]

Bob,

Don't worry;  it's called old age.  I have it in spades.

Dave
(Manta)

[Bob]

LOL ! INDEED !