Sometimes it is optimal to group keywords into tight groups.
For example when paying for pay per click ads you can group similar
keywords into a group and show the same ad for those keywords.
This tool will help you accomplish that with only a few clicks.
Load in your keywords and click the "Group Keywords" button.
For large list of keywords this may take a a few seconds.
You will get back a tree list of groups.
You can the select the groups you would like to copy, right-click
on one of them and click Copy.
Look at the screenshot below to see this tool in action: