This handy little app provides all the features of PowerMenu, plus the file-dialog quick-menus that PowerDesk's Dialog Helper used to do, plus a whole pack of extras: minimize-to-floating icon, a virtual desktops plugin, etc, Seriously useful stuff.
SourceCode and Compiled Binaries for two low-level system information tools: NtSysInfo explores Windows internals and enumerates system processes, windows, threads, objects. The WhoUses utility allows you to determine what process has a file or DLL locked.
The Network Protocol sniffer formerly known as Ethereal. Live capture tool allows offline analysis ad can read data from ethernet, bluetooth, usb, etc ... and supports every protocol I can think of.