With all the work I do on Windows Server knowing these commands is a real time saver instead of always having to run things down through the GUI. This isn't by any means a full list but here is a list of some of the things you can access in Windows without the mouse (type these at a Run Prompt):
control = Opens the Control Panel Window
control admintools = Opens the Administrative Tools
control keyboard = Opens the Keyboard Properties Window
control color = Opens the Display Properties (at the Appearance Tab in Windows 7)
control folders = Opens the Folder Options Window
control fonts = Opens the Font Policy Management Window
control international (or intl.cpl) = Opens Regional and Language Options
control mouse (or main.cpl) Opens mouse properties
control userpasswords = Opens the User Accounts Editor
control userpasswords2 (or netplwiz) = Opens User Account Access Restrictions
control printers = Opens the Printers and Faxes Window
control desktop (Windows Vista/7 only) = Opens Control Panel>Personalization
appwiz.cpl = Opens the Add or Remove Programs Utility
optionalfeatures = opens the Add or Remove Windows Component utility
desk.cpl = Opens the Display Properties (Themes Tab)
hdwwiz.cpl = Opens the Add Hardware Wizard
irprops.cpl = Opens the Infrared utility (does nothing if no IR devices are installed)
joy.cpl = Opens Game Controller Settings
mmsys.cpl = Opens the Sound and Audio device properties window (Volume Tab)
sysdm.cpl = Opens the System Properties window
telephon.cpl = Opens the Phone and Modem options window
timedate.cpl = Opens the Date and Time Properties window
wscui.cpl = Opens the Windows Security Center in XP (opens the Action Center in Windows Vista/7)
access.cpl = Opens the Accessibility Options Window (does not work in Windows 7)
wuaucpl.cpl = Opens Automatic Updates
powercfg.cpl = Opens the Power Options Properties window
ncpa.cpl = Opens the Network Connections window
bthprops.cpl = Opens the Bluetooth Control window (does nothing if no bluetooth devices are installed)
certmgr.msc = Opens the Certificate Management MMC
compmgmt.msc = Opens the Computer Management
comexp.msc (or dcomcnfg) = Opens the Computer Services MMC
devmgmt.msc = Opens Device Manager
diskmgmt.msc = Opens Disk Management
eventvwr.msc (or eventvwr) = Opens the Event Viewer
fsmgmt.msc = Opens Shared Folders
napclcfg.msc = Opens the NAP client configuration tool
services.msc = Opens Service Manager
taskschd.msc (or control schedtasks) = Opens the Task Scheduler
gpedit.msc = Opens the Group Policy MMC
lusrmgr.msc = Opens Local Users and Groups
secpol.msc = Opens the Local Security Settings window
ciadv.msc = Opens the Indexing Service Window
ntmsmgr.msc = Opens the Removable Storage Manager
ntmsoprq.msc = Opens the Removable Storage Operator Requests
wmimgmt.msc = Opens the WMI (Windows Management Instrumentation) window
perfmon.msc (or perfmon) = Opens the Performance Monitor
mmc = Opens a blank Microsoft Management Console
mdsched = Opens the Memory Diagnostics tools
dxdiag = Opens DirectX diagnostics tools
odbcad32 = Opens the ODBC Data Source Administration window
regedit (or regedt32) = Opens the Registry Editor (these commands actually open different Registry editors, google for the differences)
drwtsn32 = Opens Dr. Watson
verifier = Opens the Driver Verification Manager
cliconfg = Opens the SQL Server Client Network Utility
utilman = Opens the Utility Manager (in Windows 7 this opens the Ease Of Access Center)
msconfig = Opens the System Configuration Utility
sysedit = Opens the System Configuration Editor
syskey = Opens the Windows Account Database Security Manager
explorer = Opens Windows Explorer
iexplorer = Opens Internet Explorer
wab = Opens the Windows Address Book
charmap = Opens the Character Map
write = Opens Wordpad
