Energy storage in primary?

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Jolyon Vater Cox by way of Terry Fritz <teslalist-at-qwest-dot-net>" <jolyon-at-vatercox.freeserve.co.uk>

Is it possible to build a TC where energy is stored initially as high 
current in an inductor (the primary) rather than high voltage in a capacitor?
I am thinking of a setup where current ramps up slowly through the inductor 
before being abruptly switched off (by semiconductor switch or similar) 
after a predetermined current or period of time has been exceeded; the 
current in the primary rising and falling as "saw-tooth" waveform.

As primary input power for this would be largely determined be current 
rather than the voltage of the PSU
how high would the current have to be/ how low could the voltage be for 
decent spark output say, a minimum of 6 inches or more?

For the control logic would this likely need an exotic switch-mode power 
supply IC with PWM and dead-time control or could a simple astable like a 
555 do the job?

For the high-current, high-speed switch would bipolar transistors (e.g.. TV 
line-output power devices) or MOSFETS be suitable or would IGBTs be necessary?

Would it not be necessary to connect a capacitor across the switch to 
absorb/slow down the high-voltage transient produced when the switch opens/ 
would necessary voltage rating of switch and capacitor be comparable to 
that of the primary capacitor in a conventional spark-gap TC?