Yes netbios is a really interesting thing and really easy to use.I really liked to congratulate the tutorial and the detailed way you explained,since many people are trying and probably accessing hard drives and shares because of what you wrote.You should had wrote too the ways to protect like establishing password,use firewall to close the ports 137,138,139,and disable the file and printer sharing.You should say that this kind of access is not very stealth and can get you in trouble.you could have mentioned too that alot of smart people shares camouflaged trojans under other file formats besides exec and that these appear many times as a desirable information like passwords and account informations.You could probably have said that this is a good way to people who access this way to see their systems permanently destroyed.Its easy and sometimes very fun to use the netbios/nbtstat to check some boxes but don´t forget the people that see in this the possibility to infect others.i have seen this happening many times.Some animal fakes death,the vultures come near to feed and end to be food.