Keyword Spelling Mistakes
Many people have difficulty spelling, make typing mistakes when entering keywords or simply write words in a different way, for example, the word "color" in the US is written as "Colour" in Australia.
You can take advantage of this by targeting commonly misspelled keywords. These keywords are often far less competitive than the correctly spelled keyword.
If we go back to our Sydney Hotel example, lets try and find the different ways people spell the word accommodation. To do this, use the query: spell:accommodation
Note, the different ways in which people misspelled "accommodation".
If you target the common keyword misspellings in your PPC campaigns and even in organic SEO, you can get a real edge over your competition.