Net Tools

[LA_MERC_th33_r00k]

Cool little set of Network testing and analyzing tools (http://users.telenet.be/ahmadi/nettools.htm)that is free.

I like it and have used a few out of the list.

[LA_MERC_T4rg3T]

I've used this site forever and was pissed when they started to charge for a few options. Still has some good free tools plus it's online

http://www.dnsstuff.com/tools