The Google wonder wheel:

go to google and type in a key word, example “tablet computer”

when you get the results just under the Google search you will see “web + show options” click this and you’ll get a new left column with lots of options.

go to this list utill you see “wonder wheel” now click this

you will get what looks like a wheel with key words related to what you have just searched.

Now select on of the key words to get even more targeted information so in this example click on “apple tablet pc” and you’ll get some long tailed keywords.

Now you can use this information for your SEO or add campaignes.

Also check out the “Related searches” and “Time line” options on the left hand side

How cool is this? Have fun

ps if you are looking for Tablet Computers check this site out – Tablet Computer Review