James Grimmelmann's recent write up is worth reading http://works.bepress.com/cgi/viewcontent.cgi?article=1035&context=james_grimmelmann j
Octal gave a talk at Defcon or HOPE a few years in a row about Sealand. The last one he spilled the beans on how bad Sealand did. Managerial and customer base wise. IIRC for months the entire internet connection was done over a cell phone at 9600bps or some such. He went into some details about difficulties of the idea (banks won't accept you.) One of the most memorable talks I've seen.
- Ethan O'Toole