I just bought a new router and installed DD-WRT on it so I could use a VPN like http://hidemyass.com/.
Does any Freeper using a VPN have any advice?
Yes.
Do not rely on anything to preserve your anonymity when you access the internet.
At the level of the National Government, the internet is pretty much an open book - especially in the US. Most screen names can be traced to their authors within a few seconds, regardless of what countermeasures that you use. At best you might hold off a trace for a few minutes.
VPN relay servers merely act as registration agents for the Agencies. You might just as well send them your name and address.
Just look up stuff in Utah. All your internet belongs to us.
What if someone listens to packets going to and coming from HMA? They would easily see your traffic just as much if they simply monitored your Internet connection. Wait...what if they simply monitor your Internet connection via your ISP?
Anyone thinking there is any way possible to hide your Internet traffic has no clue how HTTP works.