Hoster is an ultra-groovy Hosts file Manager, Editor and Helper.

Some of the features of this software are:

Append File - Allows selection of a file to be appended to your current hosts file.
Replace File - Allows selection of a file to replace your hosts file.
Merge File - Allows selection of a file to be merged with your current hosts file.
Create Backup - Creates a Backup of you current hosts file. Backup file will be placed where ever Hoster.exe resides on your Hard drive.
Restore Backup - Restores the backup hosts file.
Restore MS Hosts - Restores the hosts file to Microsoft’s original hosts file.
Add to Hosts Files - Adds the line item into your hosts file.
Delete Line - Deletes highlighted line from hosts file.
Toggle Comment - Toggles whether or not a line is a comment (’#').
Sort File - Sorts the current hosts file in alphanumeric order, removes all comment lines.
Swap Localhost - Swaps the current hosts file between 127.0.0.1 and 0.0.0.0
Remove Block Items - Removes all blocking lines in the current hosts file.
Copy to Clipboard - Copies the current hosts file to the clipboard.
Make Hosts read-only/writable toggle

This is surely a nice GUI based Host File manager.

Hoster Homepage