This thread contains a list of all the keyboard shortcuts (that I'm aware of) that will help your computer experience much easier (and faster, that's why they're called "shortcuts") to work with.
I will be updating this list as I discover/remember more.
All the shortcuts listed below have been tested on Windows 8, but will most likely work for earlier versions of Windows.
Ctrl + C - Copy.
Ctrl + X - Cut.
Ctrl + V - Paste.
Ctrl + A - Select all.
Ctrl + S - Save.
Ctrl + Alt + Del(ete) - Open up task manager/other options.
Browser related -
Ctrl + T - New tab (Firefox, Chrome, IE, and most other browsers)
Ctrl + Shift + T - Undo close tab/recover your last closed tab(s).
Ctrl + W - Close tab.
Ctrl + Shift + P (Firefox) - Enter private browsing.
Ctrl + Shift + N (Chrome) - Enter incognito mode.