Ctrl + / Ctrl - or CTRL-Mouse wheel to zoom in / zoom out page
Press / to search
Ctrl-T to open new tab
Ctrl + Mouse Click to open URL in new tab
Ctrl-[1-9] to switch tab (Alt-[1-9] under X Window)
Type about:config in location bar for tweaking
My Firefox Extensions
All-in-One Gestures (Linux and Windows)
Auto Copy (Windows)
Context Search (Linux and Windows)
DragToTab (Linux and Windows)
Flash Got (Windows)
ieview (Windows)
Minimize to Tray (Windows)
Paste and Go (Windows)
ref. http://hemiolapei.free.fr/divers/mozilla.html