Well, if we're including Plot Untwists, I had Vatman flash-fry him with heat vision...
And then there was the
Imbalance Spiral Ending in which he died, along with the Churches and assorted goons, in a gas explosion ignited by his cigar. The mechanics of the explosion itself are slightly complicated, so I suggest you go and read the SE if you want the details (check the ToC for its location).
Hmm... I'm starting to see a trend here.
Phil, musing on other ways to cook a Lex (Microwaves? Lasers? Afterburners? All 3 at once?)