Interesting site, many nice kits and electronics toys here. Check out this Tesla HV generator board. Output is 800 X the input voltage. Comes as a kit.
WARNING: THIS TYPE OF CIRCUIT BOARD IS QUITE LETHAL AND NEEDS RESPECT. EXTREMELY HIGH VOLTAGE AND CURRENT.
IF YOU PLAN TO WORK WITH HIGH VOLTAGE EXPERIMENTAL CIRCUITS LIKE THIS, TAKE PRECAUTIONS AND USE PERSPEX COVERS OVER ALL OUTPUT LEADS TO PROTECT PEOPLE FROM COMING INTO CONTACT WITH THE WIRES AND HIGH VOLTAGE.
There are many other kits and boards available. Check out the site.