A very good post from Jason Kuznicki at the Positive Liberty blog. It is a response to criticism that libertarians are essentially corporate/big business shills. Two main points that Jason raises against this view:
1) libertarians argue for policies that make possible increased prosperity for everyone, not just the wealthy.
2) libertarians argue for policies that restrict any individual or groups of individuals (corporations) from making use of the power of government for their own gain.
In short, while many of the policies advocated by libertarians would benefit corporations and 'the wealthy', they also help the 'little guy'(and arguably to a much greater extent). And the justification of such policies are not in order to benefit either group as such, but to allow the greatest extent of individual liberty.
Like many of the posts at Positive Liberty, there is a lot of other very interesting and good thoughts in Jason's post. Read it.
Update 6/7/07 7:40pm: Timothy Sandefur, also at Positive Liberty, has an equally good follow up post. Refering to libertarianism, "We look toward something new–toward the future, not the past. Our ideas are new and untried paths to wealth and peace, and we ought to advocate them in precisely those terms."