[deb0and]

Also don't forget about the -P0 option, disabling ping.

Then of course there is the NSE (Nmap Scripting Engine) which makes recon even easier

Nmap isn't really the best solution to use nowadays, although it does have it's uses.

I find nmap slow when scanning large IP ranges, so for this task if anyone is interested, I use unicornscan and let me tell you this tool is powerful and extremely quick and accurate.