Common keyboard shortcuts for Cut, Copy and Paste

Generic/Apple
Cut: command-X
Copy: command-C
Paste: command-V

Windows/GNOME/KDE
Cut: control-X / shift-Delete
Copy: control-C / control-Insert
Paste: control-V / shift-Insert

BeOS
Cut: alt-X
Copy: alt-C
Paste: alt-V

Common User Access
Cut: shift+Delete
Copy: control+Insert
Paste: shift+Insert

Emacs
Cut: control-W (to mark) control-K (to end of line)
Copy: meta-W (to mark)
Paste: control-Y

vi
Cut: d (delete)
Copy: y (yank)
Paste: p (put)

X Window System
Cut:
Copy: click-and-drag to highlight
Paste: middle mouse button