Simplified ES generator with added capacitors and flash
light (measured breakdown ~ 6.5 kV). Common 9V battery to power motor and turn the disc. The disc can also be turned by hand and the charge builds up very quickly.

Video:

The video was done a second time because in the first try there
was to much background light for the camera to capture the sparks. It's better now but still missing a lot - listen to the sound.

Designed and built within two days (weekend) and to be seen

as a draft version, this little machine produces a lot of current @ high voltage - always be careful!
 
The blue wires are contacting the disc. Either thin lize wire or
carbon fibre (better), the green wires end in close proximity to the
disc and do not touch.

Connection:
blue/top/left - connected to aluminium plate directly behind
blue/bottom/left - connects to blue/top/right
blue/bottom/right - connected to aluminium plate directly behind
green wires are output - connected with capacitor legs, parallel is the flash light or spark gap (discharges bad for your ears)

What learned - slower is better. Hyperspeed as shown in the video is nonsense. A lot of loses through fine blue mesh all over the segments (seen in the dark). Next machine might be smaller - or not depends if this discharges can be reduced somehow.