Go

According to the developer, "All the simple command lines I've found have either option after option after option or are too easy to close accidentally or come in many pieces (.DLL, .HLP, .INI, etc) or are large files or skinned or shareware or require installation, etc. 'Go' is [a simple shell replacement solution; it is] one file, requires no install or uninstall, leaves nothing behind when deleted, requires no special DLL files, and can only be closed by a single route, "!quit". 'Go' is set to idle CPU usage which means it doesn't gulp your runtimes. 'Go' can be used as a shell, which means you can start with system resources above 90% (mileage may vary). 'Go' supports 36 hotkey application launches via shortcuts within Go's own home folder." For more info, check the link below.

http://www.shellcity.net/go/go.htm

Fix My Xp

A site we like -- plenty of power tweaks.

http://www.fixmyxp.com/