And is (peacefully) working to eliminate gov't illegal in and of it's self? Could congress vote to dissolve, or amend the constitution to massively reduce the size and scope of the gov't?

It generally isn't, no. In fact under a modern view of the First Amendment, even organizing with an eventual goal of a revolutionary overthrow of the government isn't illegal, as long as it doesn't rise to the level of inciting "imminent lawless action". So, prosecuting communists solely for joining a communist party and advocating communist revolution wasn't allowed after 1969 (http://en.wikipedia.org/wiki/Brandenburg_v._Ohio).

Curiously, communists probably had it better precisely because of how focused they were on the one "big" goal (communist revolution): Leninist parties in particular were very centralized, disciplined, and scrupulously avoided doing minor illegal things (vandalism, etc.) that could give the police a excuse, because Marxist-Leninist ideology generally believes that small-scale direct action is ineffective, and the vanguard party should keep its powder dry, so to speak, until they're in position to seize power in one quick move. Anarchists are much more decentralized, and have varying opinions about how to organize change, so there's much more scope for the cops to find someone who spray-painted or vandalized something, and via that argue that any group that person was part of is part of an "anarchist criminal cell" by transitivity (occasionally they get tired of waiting, and a police infiltrator will actively egg on more militancy).

This is probably off topic, but it makes an interesting contrast: in Afganistan and Pakistan, where the Bill of Rights doesn't restrict the U.S. gov, trying to peacefully express disagreement with the U.S. government's policies gets you drone bombed.

To be fair, pretty much anything you do in Pakistan can get you drone bombed, even if it's as simple as going to a wedding party or working in a hospital.

Rand was a minarchist, not an anarchist; in any case.

True, maybe Murray Rothbard would've been a better example of a "right" anarchist than Rand.

Lest anyone forget, "keeping tabs on anarchists" would also mean spying on people who are more in line with people like Noam Chomsky. There is a huge spectrum of ideology and "danger" that is encompassed by "anarchist".