Someone who values their freedom, hates the government interfering in their lives, but also doesn't trust the private sector to always do the right thing. On economic issues, they're a capitalist with reservations. They realize, for example, that quite a few people do need money to pay for healthcare, but on the other side hate the idea of socialized medicine. On most other issues, they believe in the "live and let live" libertarian philosophy. All liberaltarians oppose the idea of America policing the world, and also support the idea of a government that doesn't interfere with the personal lives of its citizens.
Overall, liberaltarians are socially liberal, fiscally moderate noninterventionists. Somewhere between Ron Paul and Dennis Kucinich.
Liberal: Conservatives and libertarians ignore the fact that there are still people who can't afford healthcare.
Conservative: Liberals just want to take money out of the economy to meddle in our lives and fund wasteful projects.
Libertarian: And neither of you two know how to balance a budget.
Liberaltarian: I guess that's why I'm not a conservative, libertarian, or liberal. You guys can continue pretending like theres only two or three ideologies and ignore the fact that there's people like me who think that all of those ideologies are flawed in some ways.