This might have been asked a number of times. But still, I thought It was not a big deal to have multiple accounts on Stack Overflow.
I personally have 2 accounts. I do not exactly recall why I created 2 accounts to be exact.
As I can remember, I had associated one of the accounts with my personal Gmail account and with limited access (Gmail was blocked in my previous company). I opted for a new account based on OpenID.
Now, I saw some posts, which seem to suggest, it does not go with the spirit of "SO" to have multiple accounts.
If that is the case, I would merge both the accounts, if that is possible.