I am big fan of network utilities that do many things at once. You never know what kind of obscure function you are going to need next to solve that obscure issue. Internet Maniac is good, but really old.
Can’t remember where I picked it up, but today I unpacked and tested Network Stuff – highly functional all-in-one network app.
What it does
App packs numerous network-related utilities in single interface. On the top there are tabs that represent tools, middle is working area and bottom has another row of tabs for working windows. 
Functions are grouped by network principle rather than by commonly used names. For example ping and trace route are combined under ICMP tab.
Strong features
Network Stuff packs very wide range of utilities and most of them come with precise run options.
Personally I most like that it can not only show open ports and active network applications, but even split them by protocol.
App goes extra mile and includes many less used functions, including but not limited to:
- whois database lookups;
- wake on lan;
- remote shutdown;
- highly advanced functions like virtual proxy creation and packets capture.
Downsides
The only downside to this one is that it will be poor choice for a newbie. App assumes you are acquainted with terms, protocols and makes little effort to explain.
You need to know your way around networks to use this one, not the other way around.
Overall
Most impressive set of network functions I had seen in years. Works without installation, but require .NET Framework. Open source under GPL.
Home&download http://jacquelin.potier.free.fr/networkstuff/
McAfee Site Advisor tells how safe files and links are
Simply a day for a local chat at this blog
Automate network pings with PingInfoView
NetSetMan – app for quick changes of network settings
Precisely log network ports used with Wireshark
TeamViewer – functional remote access tool
Fixing network connectivity with WinSock Fix
Mapping stuff in PersonalBrain
NetWorx – free portable network traffic monitor
Get most out of network connection with TCP Optimizer
Internet Maniac networking utility
NetResView – helper utility for shared folders
I have installed here “Simple Internet Tools – A Dozen Simple Helpful Tools” ( http://www.pcwintech.com/simple-internet-tools-dozen-simple-helpful-tools ) which provides basic but useful network tools as well, nice layout (though with per-function modules), easy to understand.
@Transcontinental
Bookmarked to check out. But screenshots are kinda scary. :) I learned to be wary of programmers who get creative with interfaces.
Think Internet Maniac is old? I still have Cyberkit by Luc Neijens around from the nineties. and it still worked, until i recently tried in on Windows 7 :-(
So this looks like a good replacement.
@rvdmast
I wasn’t even connected in nineties. :) Makes you think how damn old those network protocols are. No wonder we are running out of IPs and stuff.