First of all, I must say that ellektra hasn't always been my username. My former username was rogan_soul, because Rogan has always been my favourite OTP and they were the main reason I got into livejournal. That said, the name "ellektra" came to me when season 2 of Heroes was being shown in the usa.
In that season, a new character named Elle Bishop was introduced and I liked her from the first moment. She had the power of create and manipulate electricity. And since "electricity" was very similar to "elektra", I thought it was a nice pun and decided to change my username to ellektra, as soon as I was able to do so. Its "Elle"+"electricity"+"Elektra".