Yes he did, and the Doctor gave him an answer, in the series 3 episode "Utopia".
It's Harkness, although that is not his real name, he stole the identity of the real Captain Jack during WW1. His real identity is unknown.
John Barrowman
John Barrowman played captain jack in doctor who. :)
Jack is actually bisexual. Or omisexual if you will considering the amount of aliens on the show. He will still flirt with you whether your male or female.
Only four people know how to do that- The Doctor himself, his evil opposite number The Master (the only known other surviving Time Lord to date), Captain Jack Harkness from Torchwood, and The Doctor's daughter River Song. His companions know how to work some of it, but fall way short of being able to pilot it themselves. The TARDIS is also itself a sentient machine with organic origins, and can to some extent think for and fly itself.
Captin Jack is a fictional man, from the BBC series Doctor Who and Torchwood.
At the moment there are no plans for him to return to Doctor Who.
It was Captain Jack Harkness.
No, as of 2012 he has never currently been on Torchwood. However characters from Torchwood (mostly Captain Jack Harkness) have appeared in Doctor Who.
It's Harkness, although that is not his real name, he stole the identity of the real Captain Jack during WW1. His real identity is unknown.
John Barrowman
Torchwood - 2006 Captain Jack Harkness 1-12 is rated/received certificates of: UK:12
Captain Jack Harkness first appeared in the 2005 episode "The Empty Child" of Doctor Who's first revived series. He went on to become a recurring character and fan favorite in the show.
CAPTAIN JACK HARKNESS
There's some evidence that it may be Captain Jack Harkness.
If I am understanding your question correctly then this question is more a matter of opinion. For me the biggest "show off" would probably be Captain Jack Harkness.
John Barrowman who plays Captain Jack Harkness in Torchwood is gay in real life, he went for the part of Will in "Will and Grace" but they said that he did not look gay enough for the part.