Connectify Hotspot - Connectify Me hotspot is a PC app that turns your computer into a Wi-Fi hotspot.
tcpdump - tcpdump is a common packet analyzer that runs under the command line.
mHotspot - mHotspot is a completely free software which converts your windows 7 & 8 laptop into a virtual wifi router and creates a secure wifi hotspot.
Wireshark - Wireshark is a network protocol analyzer for Unix and Windows. It lets you capture and interactively browse the traffic running on a computer network.
Maryfi - Maryfi is a software program designed for laptops to start their own wireless hotspots.
Ettercap - Ettercap is a suite for man in the middle attacks on LAN.