[jacquesm]

I think using the term 'mafia' is pushing it.

Having connections never hurt anybody, I'd assume that having YC connections doens't hurt either. Being on HN already gives you an 'in' with plenty of YC alumni and current start-up operators so by that definition pretty much everybody has a YC connection.

You'd have to be pretty specific about what kind of connection you mean and I think you should probably try to leave references to criminal organizations out of it.

[_delirium]

In the startup context, I don't see it as having particularly negative connotations or referring directly to the criminal organization. After the "PayPal Mafia", it's become a fairly common term for just alumni of a particular startup/incubator/whatever. See e.g., this aggregator of Boston-area startup tweets: http://bostonstartupmafia.com/