superberkut: none exists currently, but I was a fan of the Su-47 aircraft, whose prototype name was Berkut, and I wanted to see it in production as a real warplane. It was so awesome, with those forward-swept wings and unequal-length tail booms, and other amazing technologies not found in other craft, especially not American fighters. I created my name from that captivating fighter, adding super to the front of it to denote the S-32 (possibly), an earlier development of the same plane. 'Berkut' is also is the name for the Golden Eagle species. There is even a singer whose stage name is Arthur Berkut. However, I only found that out after I created my username. Sadly, the Su-47 was relegated to a technology demonstrator, meaning it will never enter production, but its technologies will filter down into more conventional-looking craft from Sukhoi, the company that produced the one Su-47 prototype.
It is featured in enough warplane games to send one's head reeling... and, being a fan of those too, I regularly am reminded of it.
If I obtain GT Premium, I will most likely end up as just, 'Berkut', seeing that the S-32 is still an earlier prototype of the Su-47. Here is a picture of the plane: (That is, the Su-47)
Its predecessor, the S-32, is here: