Firefox 3 has a lot of timesaving shortcuts if you just get used to using them. Below is a collection of standard keyboard shortcuts for the Mac OSX version of Firefox 3.

Navigation
Back	Cmd + [ Cmd + Left Arrow Delete
Forward	Cmd + ] Cmd + Right Arrow Shift + Delete
Home	Option + Home
Reload Page	Cmd + R F5
Reload (override cache)	Cmd + Shift + R
Stop Loading Page	Cmd + . Esc
Current Page
Go to Bottom of Page	End Cmd + Down Arrow
Go to Top of Page	Home Cmd + Up Arrow
Move to Next Frame	F6
Move to Previous Frame	Shift + F6
Page Info	Cmd + I
Page Source	Cmd + U
Print	Cmd + P
Save Page As	Cmd + S
Zoom In	Cmd + + (plus key)
Zoom Out	Cmd + – (minus key)
Zoom Reset to 100%	Cmd + 0 (zero key)
Search
Find	Cmd + F
Find Again	Cmd + G F3
Find as You Type Link	‘ (apostrophe key)
Find as You Type Text	/
Find Previous	Shift + F3
Web Search	Cmd + K
Windows & Tabs
Close Tab	Cmd + W
Close Window	Cmd + Shift + W
Move Tab Left (when tab is focused)	Cmd + Left Arrow Cmd + Up Arrow
Move Tab Right (when tab is focused)	Cmd + Right Arrow Cmd + Down Arrow
Move Tab to Beginning (when tab is focused)	Cmd + Home
Move Tab to End (when tab is focused)	Cmd + End
New Tab	Cmd + T
New Window	Cmd + N
Next Tab	Ctrl + Tab Cmd + Opt + Right Arrow Cmd + } Ctrl + Page Down
Previous Tab	Ctrl + Shift + Tab Cmd + Opt + Left Arrow Cmd + { Ctrl + Page Up
Open Address in New Tab (from Location Bar or Search Bar)	Opt + Return
Undo Close Tab	Cmd + Shift + T
Select Tab ( 1 to 8 )	Cmd + # ( 1 to 8 )
Select Last Tab	Cmd + 9
Tools
Bookmark All Tabs	Cmd + Shift + D
Bookmark This Page	Cmd + D
Bookmarks	Cmd + B
Downloads	Cmd + J
History	Cmd + Shift + H
Clear Private Data	Cmd + Shift + Del
Miscellaneous
Select Location Bar	Cmd + L F6
Select or Manage Search Engines (when Search Bar is focused)	Opt + Up Arrow Opt + Down Arrow
Full Screen Browsing	F11
Delete Selected Autocomplete Entry	Shift + Delete
Mouse Shortcuts
Back	Opt + Scroll Down
Forward	Opt + Scroll Up
Scroll Line-by-Line	Cmd + Scroll
New Tab	Double Click on Tab Bar