Lion Tip : Auto Complete

Auto Complete a word using F5

For those of us with poor spelling or for those times when you just have a mental block, you can get the built in dictionary to suggest words to complete a word you’ve started.
As you’re typing in a word in most Apple Apps like TextEdit or iChat, press the ‘F5’ key (‘fn’ + ‘F5’ on a portable computer’s keyboard), or you can press ‘Option+Escape’ to bring up an autocomplete menu which allows you to select from various possible completions to the word you’ve started.
auto complete F5