NetSetMan is a network settings manager which can easily switch between 6 different, visually structured profiles. Pre-prescribing network settings, you no longer have to write them again when you change your network connection (for example, when you connect your home computer at work, in cafes, or frequent switching between providers).
Hamachi will allow you to establish secure direct connections to PC's that are not accessible otherwise due to the restrictions in network setup.
LanTopolog is an application that provides physical network topology discovery, visualization and monitoring.
ChrisPC DNS Switch
LanHelper can scan network at high speed and it can even detect writable or read-only shared folders with the powerful and special engine. Boot (wake up) or shut down or lock your PCs.
LastPass - service for secure and convenient stores passwords to websites and works across systems and browsers. LastPass automatically fills in saved log-ins and forms with the click of a button.
TeamViewer establishes connections to any PC or server all around the world within just a few seconds. You can remote control your partner'
Gom Player is a multimedia player which can play most of the differently encoded video formats that include AVI, DAT, MPEG, DivX, XviD, and plus more) with its own built-in codec system.
Audacity is a free audio editor that can record sounds, play sounds, import and export WAV, AIFF, and MP3 files, and more. Use it to edit your sounds using Cut, Copy, and Paste (with unlimited Undo), mix tracks, or apply effects to your recordings.
Skype is the next phenomenon from the people who brought you KaZaA. Just like KaZaA, this uses P2P (peer-to-peer) technology to connect you to other users – not to share files this time, but to talk for free with your friends.