Just change your IP address all the time..
No where near sufficient once they are interested in you. There is the MAC address -- 'Hey, Frank, max americana just connected to the Starbucks wifi at 45th and Main', not to mention various statistical profiling techniques -- such as identifying you by the homepage tabs you load, or identifying when you log in at somewhere like FR and then tracing back the connection, or even having tracking software surreptitiously loaded on your machine.