Pretty sure it is. If you need serious anonymity, like if your life depends on it, get a botnet and use the trojaned PCs as proxies. Use public WiFi, and use cheap laptops that you replace regularly and/or VMs, and don't forget to fake your MAC address. Create multiple fake personas to confuse attackers. Have stuff you write rephrased by someone else, so they can't do a corpus analysis on your writings. Do as much offline as possible. If you have to transfer information, avoid the internet. Use dedicated lines, dialup, dead drops, etc. etc.
I'm so glad I have nothing to hide.